├── .gitignore ├── LICENSE ├── README.md ├── atomic_ref └── atomic_ref.cpp ├── concepts ├── hash.cpp ├── mutex.cpp └── stop_token.cpp ├── condition_attributes └── fast_mod.cpp ├── consteval └── consteval.cpp ├── jthreads ├── background.cpp ├── jthreads.cpp └── stop_token.cpp ├── modules ├── hello.cpp └── main.cpp ├── ranges ├── stl_max_element.cpp └── stl_sort.cpp ├── spaceship └── spaceship.cpp ├── span └── span.cpp └── to_array └── to_array.cpp /.gitignore: -------------------------------------------------------------------------------- 1 | # Prerequisites 2 | *.d 3 | 4 | # Compiled Object files 5 | *.slo 6 | *.lo 7 | *.o 8 | *.obj 9 | 10 | # Precompiled Headers 11 | *.gch 12 | *.pch 13 | 14 | # Compiled Dynamic libraries 15 | *.so 16 | *.dylib 17 | *.dll 18 | 19 | # Fortran module files 20 | *.mod 21 | *.smod 22 | 23 | # Compiled Static libraries 24 | *.lai 25 | *.la 26 | *.a 27 | *.lib 28 | 29 | # Executables 30 | *.exe 31 | *.out 32 | *.app 33 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. By contrast, 15 | the GNU General Public License is intended to guarantee your freedom to 16 | share and change all versions of a program--to make sure it remains free 17 | software for all its users. We, the Free Software Foundation, use the 18 | GNU General Public License for most of our software; it applies also to 19 | any other work released this way by its authors. You can apply it to 20 | your programs, too. 21 | 22 | When we speak of free software, we are referring to freedom, not 23 | price. Our General Public Licenses are designed to make sure that you 24 | have the freedom to distribute copies of free software (and charge for 25 | them if you wish), that you receive source code or can get it if you 26 | want it, that you can change the software or use pieces of it in new 27 | free programs, and that you know you can do these things. 28 | 29 | To protect your rights, we need to prevent others from denying you 30 | these rights or asking you to surrender the rights. Therefore, you have 31 | certain responsibilities if you distribute copies of the software, or if 32 | you modify it: responsibilities to respect the freedom of others. 33 | 34 | For example, if you distribute copies of such a program, whether 35 | gratis or for a fee, you must pass on to the recipients the same 36 | freedoms that you received. You must make sure that they, too, receive 37 | or can get the source code. And you must show them these terms so they 38 | know their rights. 39 | 40 | Developers that use the GNU GPL protect your rights with two steps: 41 | (1) assert copyright on the software, and (2) offer you this License 42 | giving you legal permission to copy, distribute and/or modify it. 43 | 44 | For the developers' and authors' protection, the GPL clearly explains 45 | that there is no warranty for this free software. For both users' and 46 | authors' sake, the GPL requires that modified versions be marked as 47 | changed, so that their problems will not be attributed erroneously to 48 | authors of previous versions. 49 | 50 | Some devices are designed to deny users access to install or run 51 | modified versions of the software inside them, although the manufacturer 52 | can do so. This is fundamentally incompatible with the aim of 53 | protecting users' freedom to change the software. The systematic 54 | pattern of such abuse occurs in the area of products for individuals to 55 | use, which is precisely where it is most unacceptable. Therefore, we 56 | have designed this version of the GPL to prohibit the practice for those 57 | products. If such problems arise substantially in other domains, we 58 | stand ready to extend this provision to those domains in future versions 59 | of the GPL, as needed to protect the freedom of users. 60 | 61 | Finally, every program is threatened constantly by software patents. 62 | States should not allow patents to restrict development and use of 63 | software on general-purpose computers, but in those that do, we wish to 64 | avoid the special danger that patents applied to a free program could 65 | make it effectively proprietary. To prevent this, the GPL assures that 66 | patents cannot be used to render the program non-free. 67 | 68 | The precise terms and conditions for copying, distribution and 69 | modification follow. 70 | 71 | TERMS AND CONDITIONS 72 | 73 | 0. Definitions. 74 | 75 | "This License" refers to version 3 of the GNU General Public License. 76 | 77 | "Copyright" also means copyright-like laws that apply to other kinds of 78 | works, such as semiconductor masks. 79 | 80 | "The Program" refers to any copyrightable work licensed under this 81 | License. Each licensee is addressed as "you". "Licensees" and 82 | "recipients" may be individuals or organizations. 83 | 84 | To "modify" a work means to copy from or adapt all or part of the work 85 | in a fashion requiring copyright permission, other than the making of an 86 | exact copy. The resulting work is called a "modified version" of the 87 | earlier work or a work "based on" the earlier work. 88 | 89 | A "covered work" means either the unmodified Program or a work based 90 | on the Program. 91 | 92 | To "propagate" a work means to do anything with it that, without 93 | permission, would make you directly or secondarily liable for 94 | infringement under applicable copyright law, except executing it on a 95 | computer or modifying a private copy. Propagation includes copying, 96 | distribution (with or without modification), making available to the 97 | public, and in some countries other activities as well. 98 | 99 | To "convey" a work means any kind of propagation that enables other 100 | parties to make or receive copies. Mere interaction with a user through 101 | a computer network, with no transfer of a copy, is not conveying. 102 | 103 | An interactive user interface displays "Appropriate Legal Notices" 104 | to the extent that it includes a convenient and prominently visible 105 | feature that (1) displays an appropriate copyright notice, and (2) 106 | tells the user that there is no warranty for the work (except to the 107 | extent that warranties are provided), that licensees may convey the 108 | work under this License, and how to view a copy of this License. If 109 | the interface presents a list of user commands or options, such as a 110 | menu, a prominent item in the list meets this criterion. 111 | 112 | 1. Source Code. 113 | 114 | The "source code" for a work means the preferred form of the work 115 | for making modifications to it. "Object code" means any non-source 116 | form of a work. 117 | 118 | A "Standard Interface" means an interface that either is an official 119 | standard defined by a recognized standards body, or, in the case of 120 | interfaces specified for a particular programming language, one that 121 | is widely used among developers working in that language. 122 | 123 | The "System Libraries" of an executable work include anything, other 124 | than the work as a whole, that (a) is included in the normal form of 125 | packaging a Major Component, but which is not part of that Major 126 | Component, and (b) serves only to enable use of the work with that 127 | Major Component, or to implement a Standard Interface for which an 128 | implementation is available to the public in source code form. A 129 | "Major Component", in this context, means a major essential component 130 | (kernel, window system, and so on) of the specific operating system 131 | (if any) on which the executable work runs, or a compiler used to 132 | produce the work, or an object code interpreter used to run it. 133 | 134 | The "Corresponding Source" for a work in object code form means all 135 | the source code needed to generate, install, and (for an executable 136 | work) run the object code and to modify the work, including scripts to 137 | control those activities. However, it does not include the work's 138 | System Libraries, or general-purpose tools or generally available free 139 | programs which are used unmodified in performing those activities but 140 | which are not part of the work. For example, Corresponding Source 141 | includes interface definition files associated with source files for 142 | the work, and the source code for shared libraries and dynamically 143 | linked subprograms that the work is specifically designed to require, 144 | such as by intimate data communication or control flow between those 145 | subprograms and other parts of the work. 146 | 147 | The Corresponding Source need not include anything that users 148 | can regenerate automatically from other parts of the Corresponding 149 | Source. 150 | 151 | The Corresponding Source for a work in source code form is that 152 | same work. 153 | 154 | 2. Basic Permissions. 155 | 156 | All rights granted under this License are granted for the term of 157 | copyright on the Program, and are irrevocable provided the stated 158 | conditions are met. This License explicitly affirms your unlimited 159 | permission to run the unmodified Program. The output from running a 160 | covered work is covered by this License only if the output, given its 161 | content, constitutes a covered work. This License acknowledges your 162 | rights of fair use or other equivalent, as provided by copyright law. 163 | 164 | You may make, run and propagate covered works that you do not 165 | convey, without conditions so long as your license otherwise remains 166 | in force. You may convey covered works to others for the sole purpose 167 | of having them make modifications exclusively for you, or provide you 168 | with facilities for running those works, provided that you comply with 169 | the terms of this License in conveying all material for which you do 170 | not control copyright. Those thus making or running the covered works 171 | for you must do so exclusively on your behalf, under your direction 172 | and control, on terms that prohibit them from making any copies of 173 | your copyrighted material outside their relationship with you. 174 | 175 | Conveying under any other circumstances is permitted solely under 176 | the conditions stated below. Sublicensing is not allowed; section 10 177 | makes it unnecessary. 178 | 179 | 3. Protecting Users' Legal Rights From Anti-Circumvention Law. 180 | 181 | No covered work shall be deemed part of an effective technological 182 | measure under any applicable law fulfilling obligations under article 183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or 184 | similar laws prohibiting or restricting circumvention of such 185 | measures. 186 | 187 | When you convey a covered work, you waive any legal power to forbid 188 | circumvention of technological measures to the extent such circumvention 189 | is effected by exercising rights under this License with respect to 190 | the covered work, and you disclaim any intention to limit operation or 191 | modification of the work as a means of enforcing, against the work's 192 | users, your or third parties' legal rights to forbid circumvention of 193 | technological measures. 194 | 195 | 4. Conveying Verbatim Copies. 196 | 197 | You may convey verbatim copies of the Program's source code as you 198 | receive it, in any medium, provided that you conspicuously and 199 | appropriately publish on each copy an appropriate copyright notice; 200 | keep intact all notices stating that this License and any 201 | non-permissive terms added in accord with section 7 apply to the code; 202 | keep intact all notices of the absence of any warranty; and give all 203 | recipients a copy of this License along with the Program. 204 | 205 | You may charge any price or no price for each copy that you convey, 206 | and you may offer support or warranty protection for a fee. 207 | 208 | 5. Conveying Modified Source Versions. 209 | 210 | You may convey a work based on the Program, or the modifications to 211 | produce it from the Program, in the form of source code under the 212 | terms of section 4, provided that you also meet all of these conditions: 213 | 214 | a) The work must carry prominent notices stating that you modified 215 | it, and giving a relevant date. 216 | 217 | b) The work must carry prominent notices stating that it is 218 | released under this License and any conditions added under section 219 | 7. This requirement modifies the requirement in section 4 to 220 | "keep intact all notices". 221 | 222 | c) You must license the entire work, as a whole, under this 223 | License to anyone who comes into possession of a copy. This 224 | License will therefore apply, along with any applicable section 7 225 | additional terms, to the whole of the work, and all its parts, 226 | regardless of how they are packaged. This License gives no 227 | permission to license the work in any other way, but it does not 228 | invalidate such permission if you have separately received it. 229 | 230 | d) If the work has interactive user interfaces, each must display 231 | Appropriate Legal Notices; however, if the Program has interactive 232 | interfaces that do not display Appropriate Legal Notices, your 233 | work need not make them do so. 234 | 235 | A compilation of a covered work with other separate and independent 236 | works, which are not by their nature extensions of the covered work, 237 | and which are not combined with it such as to form a larger program, 238 | in or on a volume of a storage or distribution medium, is called an 239 | "aggregate" if the compilation and its resulting copyright are not 240 | used to limit the access or legal rights of the compilation's users 241 | beyond what the individual works permit. Inclusion of a covered work 242 | in an aggregate does not cause this License to apply to the other 243 | parts of the aggregate. 244 | 245 | 6. Conveying Non-Source Forms. 246 | 247 | You may convey a covered work in object code form under the terms 248 | of sections 4 and 5, provided that you also convey the 249 | machine-readable Corresponding Source under the terms of this License, 250 | in one of these ways: 251 | 252 | a) Convey the object code in, or embodied in, a physical product 253 | (including a physical distribution medium), accompanied by the 254 | Corresponding Source fixed on a durable physical medium 255 | customarily used for software interchange. 256 | 257 | b) Convey the object code in, or embodied in, a physical product 258 | (including a physical distribution medium), accompanied by a 259 | written offer, valid for at least three years and valid for as 260 | long as you offer spare parts or customer support for that product 261 | model, to give anyone who possesses the object code either (1) a 262 | copy of the Corresponding Source for all the software in the 263 | product that is covered by this License, on a durable physical 264 | medium customarily used for software interchange, for a price no 265 | more than your reasonable cost of physically performing this 266 | conveying of source, or (2) access to copy the 267 | Corresponding Source from a network server at no charge. 268 | 269 | c) Convey individual copies of the object code with a copy of the 270 | written offer to provide the Corresponding Source. This 271 | alternative is allowed only occasionally and noncommercially, and 272 | only if you received the object code with such an offer, in accord 273 | with subsection 6b. 274 | 275 | d) Convey the object code by offering access from a designated 276 | place (gratis or for a charge), and offer equivalent access to the 277 | Corresponding Source in the same way through the same place at no 278 | further charge. You need not require recipients to copy the 279 | Corresponding Source along with the object code. If the place to 280 | copy the object code is a network server, the Corresponding Source 281 | may be on a different server (operated by you or a third party) 282 | that supports equivalent copying facilities, provided you maintain 283 | clear directions next to the object code saying where to find the 284 | Corresponding Source. Regardless of what server hosts the 285 | Corresponding Source, you remain obligated to ensure that it is 286 | available for as long as needed to satisfy these requirements. 287 | 288 | e) Convey the object code using peer-to-peer transmission, provided 289 | you inform other peers where the object code and Corresponding 290 | Source of the work are being offered to the general public at no 291 | charge under subsection 6d. 292 | 293 | A separable portion of the object code, whose source code is excluded 294 | from the Corresponding Source as a System Library, need not be 295 | included in conveying the object code work. 296 | 297 | A "User Product" is either (1) a "consumer product", which means any 298 | tangible personal property which is normally used for personal, family, 299 | or household purposes, or (2) anything designed or sold for incorporation 300 | into a dwelling. In determining whether a product is a consumer product, 301 | doubtful cases shall be resolved in favor of coverage. For a particular 302 | product received by a particular user, "normally used" refers to a 303 | typical or common use of that class of product, regardless of the status 304 | of the particular user or of the way in which the particular user 305 | actually uses, or expects or is expected to use, the product. A product 306 | is a consumer product regardless of whether the product has substantial 307 | commercial, industrial or non-consumer uses, unless such uses represent 308 | the only significant mode of use of the product. 309 | 310 | "Installation Information" for a User Product means any methods, 311 | procedures, authorization keys, or other information required to install 312 | and execute modified versions of a covered work in that User Product from 313 | a modified version of its Corresponding Source. The information must 314 | suffice to ensure that the continued functioning of the modified object 315 | code is in no case prevented or interfered with solely because 316 | modification has been made. 317 | 318 | If you convey an object code work under this section in, or with, or 319 | specifically for use in, a User Product, and the conveying occurs as 320 | part of a transaction in which the right of possession and use of the 321 | User Product is transferred to the recipient in perpetuity or for a 322 | fixed term (regardless of how the transaction is characterized), the 323 | Corresponding Source conveyed under this section must be accompanied 324 | by the Installation Information. But this requirement does not apply 325 | if neither you nor any third party retains the ability to install 326 | modified object code on the User Product (for example, the work has 327 | been installed in ROM). 328 | 329 | The requirement to provide Installation Information does not include a 330 | requirement to continue to provide support service, warranty, or updates 331 | for a work that has been modified or installed by the recipient, or for 332 | the User Product in which it has been modified or installed. Access to a 333 | network may be denied when the modification itself materially and 334 | adversely affects the operation of the network or violates the rules and 335 | protocols for communication across the network. 336 | 337 | Corresponding Source conveyed, and Installation Information provided, 338 | in accord with this section must be in a format that is publicly 339 | documented (and with an implementation available to the public in 340 | source code form), and must require no special password or key for 341 | unpacking, reading or copying. 342 | 343 | 7. Additional Terms. 344 | 345 | "Additional permissions" are terms that supplement the terms of this 346 | License by making exceptions from one or more of its conditions. 347 | Additional permissions that are applicable to the entire Program shall 348 | be treated as though they were included in this License, to the extent 349 | that they are valid under applicable law. If additional permissions 350 | apply only to part of the Program, that part may be used separately 351 | under those permissions, but the entire Program remains governed by 352 | this License without regard to the additional permissions. 353 | 354 | When you convey a copy of a covered work, you may at your option 355 | remove any additional permissions from that copy, or from any part of 356 | it. (Additional permissions may be written to require their own 357 | removal in certain cases when you modify the work.) You may place 358 | additional permissions on material, added by you to a covered work, 359 | for which you have or can give appropriate copyright permission. 360 | 361 | Notwithstanding any other provision of this License, for material you 362 | add to a covered work, you may (if authorized by the copyright holders of 363 | that material) supplement the terms of this License with terms: 364 | 365 | a) Disclaiming warranty or limiting liability differently from the 366 | terms of sections 15 and 16 of this License; or 367 | 368 | b) Requiring preservation of specified reasonable legal notices or 369 | author attributions in that material or in the Appropriate Legal 370 | Notices displayed by works containing it; or 371 | 372 | c) Prohibiting misrepresentation of the origin of that material, or 373 | requiring that modified versions of such material be marked in 374 | reasonable ways as different from the original version; or 375 | 376 | d) Limiting the use for publicity purposes of names of licensors or 377 | authors of the material; or 378 | 379 | e) Declining to grant rights under trademark law for use of some 380 | trade names, trademarks, or service marks; or 381 | 382 | f) Requiring indemnification of licensors and authors of that 383 | material by anyone who conveys the material (or modified versions of 384 | it) with contractual assumptions of liability to the recipient, for 385 | any liability that these contractual assumptions directly impose on 386 | those licensors and authors. 387 | 388 | All other non-permissive additional terms are considered "further 389 | restrictions" within the meaning of section 10. If the Program as you 390 | received it, or any part of it, contains a notice stating that it is 391 | governed by this License along with a term that is a further 392 | restriction, you may remove that term. If a license document contains 393 | a further restriction but permits relicensing or conveying under this 394 | License, you may add to a covered work material governed by the terms 395 | of that license document, provided that the further restriction does 396 | not survive such relicensing or conveying. 397 | 398 | If you add terms to a covered work in accord with this section, you 399 | must place, in the relevant source files, a statement of the 400 | additional terms that apply to those files, or a notice indicating 401 | where to find the applicable terms. 402 | 403 | Additional terms, permissive or non-permissive, may be stated in the 404 | form of a separately written license, or stated as exceptions; 405 | the above requirements apply either way. 406 | 407 | 8. Termination. 408 | 409 | You may not propagate or modify a covered work except as expressly 410 | provided under this License. Any attempt otherwise to propagate or 411 | modify it is void, and will automatically terminate your rights under 412 | this License (including any patent licenses granted under the third 413 | paragraph of section 11). 414 | 415 | However, if you cease all violation of this License, then your 416 | license from a particular copyright holder is reinstated (a) 417 | provisionally, unless and until the copyright holder explicitly and 418 | finally terminates your license, and (b) permanently, if the copyright 419 | holder fails to notify you of the violation by some reasonable means 420 | prior to 60 days after the cessation. 421 | 422 | Moreover, your license from a particular copyright holder is 423 | reinstated permanently if the copyright holder notifies you of the 424 | violation by some reasonable means, this is the first time you have 425 | received notice of violation of this License (for any work) from that 426 | copyright holder, and you cure the violation prior to 30 days after 427 | your receipt of the notice. 428 | 429 | Termination of your rights under this section does not terminate the 430 | licenses of parties who have received copies or rights from you under 431 | this License. If your rights have been terminated and not permanently 432 | reinstated, you do not qualify to receive new licenses for the same 433 | material under section 10. 434 | 435 | 9. Acceptance Not Required for Having Copies. 436 | 437 | You are not required to accept this License in order to receive or 438 | run a copy of the Program. Ancillary propagation of a covered work 439 | occurring solely as a consequence of using peer-to-peer transmission 440 | to receive a copy likewise does not require acceptance. However, 441 | nothing other than this License grants you permission to propagate or 442 | modify any covered work. These actions infringe copyright if you do 443 | not accept this License. Therefore, by modifying or propagating a 444 | covered work, you indicate your acceptance of this License to do so. 445 | 446 | 10. Automatic Licensing of Downstream Recipients. 447 | 448 | Each time you convey a covered work, the recipient automatically 449 | receives a license from the original licensors, to run, modify and 450 | propagate that work, subject to this License. You are not responsible 451 | for enforcing compliance by third parties with this License. 452 | 453 | An "entity transaction" is a transaction transferring control of an 454 | organization, or substantially all assets of one, or subdividing an 455 | organization, or merging organizations. If propagation of a covered 456 | work results from an entity transaction, each party to that 457 | transaction who receives a copy of the work also receives whatever 458 | licenses to the work the party's predecessor in interest had or could 459 | give under the previous paragraph, plus a right to possession of the 460 | Corresponding Source of the work from the predecessor in interest, if 461 | the predecessor has it or can get it with reasonable efforts. 462 | 463 | You may not impose any further restrictions on the exercise of the 464 | rights granted or affirmed under this License. For example, you may 465 | not impose a license fee, royalty, or other charge for exercise of 466 | rights granted under this License, and you may not initiate litigation 467 | (including a cross-claim or counterclaim in a lawsuit) alleging that 468 | any patent claim is infringed by making, using, selling, offering for 469 | sale, or importing the Program or any portion of it. 470 | 471 | 11. Patents. 472 | 473 | A "contributor" is a copyright holder who authorizes use under this 474 | License of the Program or a work on which the Program is based. The 475 | work thus licensed is called the contributor's "contributor version". 476 | 477 | A contributor's "essential patent claims" are all patent claims 478 | owned or controlled by the contributor, whether already acquired or 479 | hereafter acquired, that would be infringed by some manner, permitted 480 | by this License, of making, using, or selling its contributor version, 481 | but do not include claims that would be infringed only as a 482 | consequence of further modification of the contributor version. For 483 | purposes of this definition, "control" includes the right to grant 484 | patent sublicenses in a manner consistent with the requirements of 485 | this License. 486 | 487 | Each contributor grants you a non-exclusive, worldwide, royalty-free 488 | patent license under the contributor's essential patent claims, to 489 | make, use, sell, offer for sale, import and otherwise run, modify and 490 | propagate the contents of its contributor version. 491 | 492 | In the following three paragraphs, a "patent license" is any express 493 | agreement or commitment, however denominated, not to enforce a patent 494 | (such as an express permission to practice a patent or covenant not to 495 | sue for patent infringement). To "grant" such a patent license to a 496 | party means to make such an agreement or commitment not to enforce a 497 | patent against the party. 498 | 499 | If you convey a covered work, knowingly relying on a patent license, 500 | and the Corresponding Source of the work is not available for anyone 501 | to copy, free of charge and under the terms of this License, through a 502 | publicly available network server or other readily accessible means, 503 | then you must either (1) cause the Corresponding Source to be so 504 | available, or (2) arrange to deprive yourself of the benefit of the 505 | patent license for this particular work, or (3) arrange, in a manner 506 | consistent with the requirements of this License, to extend the patent 507 | license to downstream recipients. "Knowingly relying" means you have 508 | actual knowledge that, but for the patent license, your conveying the 509 | covered work in a country, or your recipient's use of the covered work 510 | in a country, would infringe one or more identifiable patents in that 511 | country that you have reason to believe are valid. 512 | 513 | If, pursuant to or in connection with a single transaction or 514 | arrangement, you convey, or propagate by procuring conveyance of, a 515 | covered work, and grant a patent license to some of the parties 516 | receiving the covered work authorizing them to use, propagate, modify 517 | or convey a specific copy of the covered work, then the patent license 518 | you grant is automatically extended to all recipients of the covered 519 | work and works based on it. 520 | 521 | A patent license is "discriminatory" if it does not include within 522 | the scope of its coverage, prohibits the exercise of, or is 523 | conditioned on the non-exercise of one or more of the rights that are 524 | specifically granted under this License. You may not convey a covered 525 | work if you are a party to an arrangement with a third party that is 526 | in the business of distributing software, under which you make payment 527 | to the third party based on the extent of your activity of conveying 528 | the work, and under which the third party grants, to any of the 529 | parties who would receive the covered work from you, a discriminatory 530 | patent license (a) in connection with copies of the covered work 531 | conveyed by you (or copies made from those copies), or (b) primarily 532 | for and in connection with specific products or compilations that 533 | contain the covered work, unless you entered into that arrangement, 534 | or that patent license was granted, prior to 28 March 2007. 535 | 536 | Nothing in this License shall be construed as excluding or limiting 537 | any implied license or other defenses to infringement that may 538 | otherwise be available to you under applicable patent law. 539 | 540 | 12. No Surrender of Others' Freedom. 541 | 542 | If conditions are imposed on you (whether by court order, agreement or 543 | otherwise) that contradict the conditions of this License, they do not 544 | excuse you from the conditions of this License. If you cannot convey a 545 | covered work so as to satisfy simultaneously your obligations under this 546 | License and any other pertinent obligations, then as a consequence you may 547 | not convey it at all. For example, if you agree to terms that obligate you 548 | to collect a royalty for further conveying from those to whom you convey 549 | the Program, the only way you could satisfy both those terms and this 550 | License would be to refrain entirely from conveying the Program. 551 | 552 | 13. Use with the GNU Affero General Public License. 553 | 554 | Notwithstanding any other provision of this License, you have 555 | permission to link or combine any covered work with a work licensed 556 | under version 3 of the GNU Affero General Public License into a single 557 | combined work, and to convey the resulting work. The terms of this 558 | License will continue to apply to the part which is the covered work, 559 | but the special requirements of the GNU Affero General Public License, 560 | section 13, concerning interaction through a network will apply to the 561 | combination as such. 562 | 563 | 14. Revised Versions of this License. 564 | 565 | The Free Software Foundation may publish revised and/or new versions of 566 | the GNU General Public License from time to time. Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. Limitation of Liability. 601 | 602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS 604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY 605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE 606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF 607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD 608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), 609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF 610 | SUCH DAMAGES. 611 | 612 | 17. Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Learning C++20 2 | A collection of code examples to show off new parts of C++20 3 | 4 | ## Contact 5 | 6 | Suggestions for specific content can be sent to: CoffeeBeforeArch@gmail.com 7 | 8 | ## Environment 9 | Operating System: Ubuntu 18.04 10 | 11 | Text Editor: VIM 12 | 13 | C++ Compiler: g++ (10.0 experimental) 14 | 15 | # Concepts covered in C++ Crash Course 16 | 17 | ## Examples 18 | | Video | Concepts | Files | 19 | | ----- | -------- | ----- | 20 | | | Selective Atomicity | | 21 | | | Conecepts | | 22 | | | Portable Branch Hints | | 23 | | | Consteval Functions | | 24 | | | Joinable Threads | | 25 | | | Range Algorithms | | 26 | | | Auto-Generated Comparison Operators | | 27 | | | Spans | | 28 | | | C-String Conversion | | 29 | -------------------------------------------------------------------------------- /atomic_ref/atomic_ref.cpp: -------------------------------------------------------------------------------- 1 | // This program shows the basics of using atomic_ref in C++ 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | 8 | int main() { 9 | // Create an integer and a atomic_ref to the integer 10 | int a = 0; 11 | std::atomic_ref ref(a); 12 | 13 | // Our lambda for multiple threads 14 | auto work = [&]() { 15 | // Increment the non-atomic int atomically! 16 | for (int i = 0; i < 10000; i++) { 17 | ref++; 18 | } 19 | }; 20 | 21 | // Create some threads 22 | std::thread t0(work); 23 | std::thread t1(work); 24 | std::thread t2(work); 25 | std::thread t3(work); 26 | 27 | // Join the threads 28 | t0.join(); 29 | t1.join(); 30 | t2.join(); 31 | t3.join(); 32 | 33 | // Print the value of our non-atomic int 34 | std::cout << "Value of a is: " << a << '\n'; 35 | 36 | return 0; 37 | } 38 | -------------------------------------------------------------------------------- /concepts/hash.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off custom concepts in C++ 2 | // By: Nick From CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | #include 8 | 9 | // For our string literal 10 | using namespace std::literals; 11 | 12 | // Here's an example of a custom concept from cppreference.com 13 | // For a given type T, we define a concept called Hashable 14 | template 15 | concept Hashable = requires(T a) { 16 | // Hashable requires the expression of hashing type T 17 | // to be convertable to size_t 18 | { std::hash{}(a) } 19 | ->std::convertible_to; 20 | }; 21 | 22 | // Here's a function where we use the concept 23 | template 24 | void func(T a) { 25 | std::cout << "Hash of type = " << std::hash{}(a) << '\n'; 26 | }; 27 | 28 | // Here's an empty struct 29 | struct empty_struct {}; 30 | 31 | int main() { 32 | // We can hash a string... 33 | func("abc"s); 34 | // But we can't hash our empty_struct! 35 | empty_struct e; 36 | func(e); 37 | 38 | return 0; 39 | } 40 | -------------------------------------------------------------------------------- /concepts/mutex.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off a custom concept in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | 8 | // For our string literal 9 | using namespace std::literals; 10 | 11 | // A simplified concept for checking equality 12 | template 13 | concept EqualityComparable = requires(T a, T b) { 14 | // We can check if the result of the expression is convertible to a bool 15 | //{ a == b } 16 | //->std::convertible_to; 17 | // We can also use another concept! 18 | a == b; requires std::boolean; 19 | }; 20 | 21 | // Here's are function we use the concept with 22 | // We can use our concept, or the standard one 23 | template 24 | // template 25 | void f(T&& t1) { 26 | if (t1 == t1) { 27 | // Empty function body 28 | } 29 | } 30 | 31 | int main() { 32 | // Call our function with a string 33 | f("abc"s); 34 | // Call our function with a mutex (fails!) 35 | std::mutex mtx; 36 | f(mtx); 37 | 38 | return 0; 39 | } 40 | -------------------------------------------------------------------------------- /concepts/stop_token.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of stop tokens in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | #include 8 | 9 | using namespace std::chrono; 10 | 11 | // Here, we constrain the type to those that are signed and integral 12 | // This helps avoid long, and non-intuitive template error messages 13 | // Instead, we get a simple one that says the constraint that failed! 14 | template 15 | void sleepFunc(T num) { 16 | std::this_thread::sleep_for(seconds(num)); 17 | } 18 | 19 | int main() { 20 | // Let's create a jthread an pass it a stop token 21 | std::jthread jt0([](std::stop_token tk) { 22 | // Print in a loop 23 | for (int i = 0; i < 10; i++) { 24 | std::cout << "Printing value: " << i << '\n'; 25 | 26 | // Stop, if that has been requested 27 | if (tk.stop_requested()) { 28 | return; 29 | } 30 | 31 | // Sleep so this doesn't finish too quickly 32 | // This should be a long int, not a double! 33 | sleepFunc(1.5); 34 | } 35 | }); 36 | 37 | // Pause the main thread before cancelling the jthread 38 | sleepFunc(5); 39 | 40 | // Request for our jthread to stop 41 | jt0.request_stop(); 42 | std::cout << "Stopped the jthread!\n"; 43 | 44 | return 0; 45 | } 46 | -------------------------------------------------------------------------------- /condition_attributes/fast_mod.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the likely and unlikely C++20 attributes 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | 8 | // Function for generating argument pairs 9 | static void custom_args(benchmark::internal::Benchmark *b) { 10 | for (int i = 1 << 4; i <= 1 << 10; i <<= 2) { 11 | // Collect stats at 1/8, 1/2, and 7/8 12 | for (int j : {32, 128, 224}) { 13 | b = b->ArgPair(i, j); 14 | } 15 | } 16 | } 17 | 18 | // Baseline for intuitive modulo operation 19 | static void baseMod(benchmark::State &s) { 20 | // Number of elements 21 | int N = s.range(0); 22 | 23 | // Max for mod operator 24 | int ceil = s.range(1); 25 | 26 | // Vector for input and output of modulo 27 | std::vector input; 28 | std::vector output; 29 | input.resize(N); 30 | output.resize(N); 31 | 32 | // Generate random inputs 33 | std::mt19937 rng; 34 | rng.seed(std::random_device()()); 35 | std::uniform_int_distribution dist(0, 255); 36 | for (int &i : input) { 37 | i = dist(rng); 38 | } 39 | 40 | while (s.KeepRunning()) { 41 | // Compute the modulo for each element 42 | for (int i = 0; i < N; i++) { 43 | output[i] = input[i] % ceil; 44 | } 45 | } 46 | } 47 | // Register the benchmark 48 | BENCHMARK(baseMod)->Apply(custom_args); 49 | 50 | // Baseline for intuitive modulo operation 51 | static void fastMod(benchmark::State &s) { 52 | // Number of elements 53 | int N = s.range(0); 54 | 55 | // Max for mod operator 56 | int ceil = s.range(1); 57 | 58 | // Vector for input and output of modulo 59 | std::vector input; 60 | std::vector output; 61 | input.resize(N); 62 | output.resize(N); 63 | 64 | // Generate random inputs 65 | std::mt19937 rng; 66 | rng.seed(std::random_device()()); 67 | std::uniform_int_distribution dist(0, 255); 68 | for (int &i : input) { 69 | i = dist(rng); 70 | } 71 | 72 | while (s.KeepRunning()) { 73 | // DON'T compute the mod for each element 74 | // Skip the expensive operation using a simple compare 75 | for (int i = 0; i < N; i++) { 76 | if (input[i] >= ceil) [[unlikely]] { 77 | output[i] = input[i] % ceil; 78 | } else { 79 | output[i] = input[i]; 80 | } 81 | } 82 | } 83 | } 84 | // Register the benchmark 85 | BENCHMARK(fastMod)->Apply(custom_args); 86 | 87 | // Benchmark main function 88 | BENCHMARK_MAIN(); 89 | -------------------------------------------------------------------------------- /consteval/consteval.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of consteval in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | 7 | // A consteval function 8 | // This MUST be evaluated at compile time 9 | consteval int fibonacci(int N) { 10 | if (N <= 1) return N; 11 | return fibonacci(N - 1) + fibonacci(N - 2); 12 | } 13 | 14 | int main() { 15 | // This works with our consteval function 16 | int val = fibonacci(22); 17 | 18 | // This does not! 19 | // val = fibonacci(rand() % 20); 20 | 21 | // Print the result 22 | std::cout << "The fibonacci number is: " << val << '\n'; 23 | 24 | return 0; 25 | } 26 | -------------------------------------------------------------------------------- /jthreads/background.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of jthreads in C++ 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | 7 | int main() { 8 | // What happens when we spawn a thread, and we don't join it? 9 | // If it's join-able, std::terminate gets called (usually calls abort) 10 | std::thread t0([]() { std::cout << "Printing from the new thread!\n"; }); 11 | 12 | // If we call join, we wait for the thread to finish 13 | // t0.join(); 14 | 15 | // If we call detach, the thread is no longer join-able (terminate isn't 16 | // called) 17 | // However, if main exits, our string may not print! 18 | t0.detach(); 19 | 20 | return 0; 21 | } 22 | -------------------------------------------------------------------------------- /jthreads/jthreads.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of jthreads in C++ 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | 7 | int main() { 8 | // Now we have jthreads! 9 | // jthreads are a new kind of thread that automatically re-join on destruction 10 | std::jthread t0([]() { std::cout << "Printing from the new thread!\n"; }); 11 | 12 | // We dont need a join here now! 13 | // But this is just one thing we get with jthreads! 14 | 15 | return 0; 16 | } 17 | -------------------------------------------------------------------------------- /jthreads/stop_token.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of stop tokens in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | 8 | using namespace std::chrono; 9 | 10 | int main() { 11 | // Let's create a jthread an pass it a stop token 12 | std::jthread jt0([](std::stop_token tk) { 13 | // Print in a loop 14 | for (int i = 0; i < 10; i++) { 15 | std::cout << "Printing value: " << i << '\n'; 16 | 17 | // Stop, if that has been requested 18 | if (tk.stop_requested()) { 19 | return; 20 | } 21 | 22 | // Sleep so this doesn't go too quickly 23 | std::this_thread::sleep_for(seconds(1)); 24 | } 25 | }); 26 | 27 | // Pause the main thread before cancelling the jthread 28 | std::this_thread::sleep_for(seconds(5)); 29 | 30 | // Request for our jthread to stop 31 | jt0.request_stop(); 32 | std::cout << "Stopped the jthread!\n"; 33 | 34 | return 0; 35 | } 36 | -------------------------------------------------------------------------------- /modules/hello.cpp: -------------------------------------------------------------------------------- 1 | module; 2 | 3 | #include 4 | #include 5 | 6 | export module hello; 7 | 8 | export void greeter(const std::string_view &name) { 9 | std::cout << "Hello, " << name << "!\n"; 10 | } 11 | -------------------------------------------------------------------------------- /modules/main.cpp: -------------------------------------------------------------------------------- 1 | // Import our greeter module 2 | import hello; 3 | 4 | int main() { 5 | greeter("world"); 6 | return 0; 7 | } 8 | -------------------------------------------------------------------------------- /ranges/stl_max_element.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off STL max element in C++ 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | #include 8 | 9 | int main() { 10 | // Number of elements to sort 11 | const unsigned N = 20; 12 | 13 | // Our vector to sort 14 | std::vector v(N); 15 | 16 | // Set up our random number generator 17 | std::mt19937 rng; 18 | rng.seed(std::random_device()()); 19 | std::uniform_int_distribution dist(0, 255); 20 | 21 | // Generate our random inputs 22 | std::ranges::generate(v, [&]() { return dist(rng); }); 23 | 24 | // Print the vector 25 | std::cout << "Elements in v: "; 26 | for (auto e : v) std::cout << e << " "; 27 | std::cout << '\n'; 28 | 29 | // Find the max element 30 | std::cout << "Max Element = " << *(std::ranges::max_element(v)) << '\n'; 31 | 32 | return 0; 33 | } 34 | -------------------------------------------------------------------------------- /ranges/stl_sort.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off STL sort in C++ 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | #include 8 | 9 | int main() { 10 | // Number of elements to sort 11 | const unsigned N = 20; 12 | 13 | // Our vector to sort 14 | std::vector v(N); 15 | 16 | // Set up our random number generator 17 | std::mt19937 rng; 18 | rng.seed(std::random_device()()); 19 | std::uniform_int_distribution dist(0, 255); 20 | 21 | // Generate our random inputs 22 | std::ranges::generate(v, [&]() { return dist(rng); }); 23 | 24 | // Dump the potentially unsorted contents 25 | std::cout << "Before: "; 26 | for (auto i : v) std::cout << i << " "; 27 | std::cout << '\n'; 28 | 29 | // Sort the vector 30 | std::ranges::sort(v); 31 | 32 | // Dump the sorted contents 33 | std::cout << "After: "; 34 | for (auto i : v) std::cout << i << " "; 35 | 36 | std::cout << '\n'; 37 | 38 | return 0; 39 | } 40 | -------------------------------------------------------------------------------- /spaceship/spaceship.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of using the spaceship operator in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | #include 7 | 8 | // A simple struct with 2 integers 9 | // How do we compare two of these structs? 10 | struct Ints { 11 | int a; 12 | int b; 13 | 14 | // The spaceship operator allows us avoid a bunch of boilerplate code! 15 | auto operator<=>(const Ints&) const = default; 16 | 17 | // Having to implement all operations like this would be a hassle! 18 | /* 19 | bool operator<(const Ints &i) { 20 | // Compare a's, then b's 21 | if (a < i.a || (a == i.a && b < i.b)) { 22 | return true; 23 | } else { 24 | return false; 25 | } 26 | } 27 | */ 28 | }; 29 | 30 | int main() { 31 | // We'll create a couple of our structs 32 | Ints t1 = {1, 2}; 33 | Ints t2 = {3, 4}; 34 | 35 | // Put them in a vector 36 | std::vector v; 37 | v.push_back(t1); 38 | v.push_back(t2); 39 | 40 | // And sort them! 41 | // std::sort() requires the '<' operator! 42 | std::sort(begin(v), end(v)); 43 | 44 | return 0; 45 | } 46 | -------------------------------------------------------------------------------- /span/span.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of spans in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | 7 | // An old-fashioned way of passing an array to a function 8 | // Easy to make mistakes, requires us to pass a value 9 | void printArray(const int a[], const int N) { 10 | for (int i = 0; i < N; i++) { 11 | std::cout << a[i] << ' '; 12 | } 13 | std::cout << '\n'; 14 | } 15 | 16 | // A modern way using spans! 17 | // It replaces pointer-length pairs with a view of contiguous storage 18 | // Allows us to use range-based for loop, find_if, etc, without any extra 19 | // overhead from a container 20 | void printSpan(std::span s) { 21 | for (auto i : s) { 22 | std::cout << i << ' '; 23 | } 24 | std::cout << '\n'; 25 | } 26 | 27 | int main() { 28 | // Create a new array and initialize it to 0 29 | int a[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; 30 | 31 | // Call a function using our array and its length 32 | printArray(a, 10); 33 | 34 | // Call the function that uses a span 35 | printSpan(a); 36 | 37 | return 0; 38 | } 39 | -------------------------------------------------------------------------------- /to_array/to_array.cpp: -------------------------------------------------------------------------------- 1 | // This program shows off the basics of std::to_array in C++20 2 | // By: Nick from CoffeeBeforeArch 3 | 4 | #include 5 | #include 6 | 7 | int main() { 8 | // What happens when we create an array like so? 9 | // We get an array with a single const char*! 10 | auto a1 = std::array{"foo"}; 11 | for (auto e : a1) std::cout << e << ' '; 12 | std::cout << '\n'; 13 | 14 | // If we want to separate the characters, we can use std::to_array 15 | auto a2 = std::to_array("foo"); 16 | for (auto e : a2) std::cout << e << ' '; 17 | std::cout << '\n'; 18 | 19 | return 0; 20 | } 21 | --------------------------------------------------------------------------------