├── .travis.yml ├── Cargo.toml ├── LICENSE-APACHE ├── LICENSE-MIT ├── README.rst ├── src └── lib.rs └── tests └── cross_crate.rs /.travis.yml: -------------------------------------------------------------------------------- 1 | language: rust 2 | sudo: false 3 | matrix: 4 | include: 5 | - rust: 1.20.0 6 | - rust: stable 7 | env: STABLE=1 8 | - rust: nightly 9 | env: STABLE=1 10 | branches: 11 | only: 12 | - master 13 | script: 14 | - | 15 | cargo build -v && 16 | cargo test -v --lib && 17 | cargo test -v --doc && 18 | cargo doc -v && 19 | ([ "$STABLE" != 1 ] || cargo test ) 20 | -------------------------------------------------------------------------------- /Cargo.toml: -------------------------------------------------------------------------------- 1 | [package] 2 | name = "defmac" 3 | version = "0.2.1" 4 | authors = ["bluss"] 5 | license = "Apache-2.0/MIT" 6 | 7 | description = "A macro to define lambda-like macros inline." 8 | 9 | documentation = "https://docs.rs/defmac/" 10 | repository = "https://github.com/bluss/defmac" 11 | categories = ["rust-patterns"] 12 | 13 | [dependencies] 14 | 15 | [package.metadata.release] 16 | no-dev-version = true 17 | tag-name = "{{version}}" 18 | -------------------------------------------------------------------------------- /LICENSE-APACHE: -------------------------------------------------------------------------------- 1 | Apache License 2 | Version 2.0, January 2004 3 | http://www.apache.org/licenses/ 4 | 5 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 6 | 7 | 1. Definitions. 8 | 9 | "License" shall mean the terms and conditions for use, reproduction, 10 | and distribution as defined by Sections 1 through 9 of this document. 11 | 12 | "Licensor" shall mean the copyright owner or entity authorized by 13 | the copyright owner that is granting the License. 14 | 15 | "Legal Entity" shall mean the union of the acting entity and all 16 | other entities that control, are controlled by, or are under common 17 | control with that entity. For the purposes of this definition, 18 | "control" means (i) the power, direct or indirect, to cause the 19 | direction or management of such entity, whether by contract or 20 | otherwise, or (ii) ownership of fifty percent (50%) or more of the 21 | outstanding shares, or (iii) beneficial ownership of such entity. 22 | 23 | "You" (or "Your") shall mean an individual or Legal Entity 24 | exercising permissions granted by this License. 25 | 26 | "Source" form shall mean the preferred form for making modifications, 27 | including but not limited to software source code, documentation 28 | source, and configuration files. 29 | 30 | "Object" form shall mean any form resulting from mechanical 31 | transformation or translation of a Source form, including but 32 | not limited to compiled object code, generated documentation, 33 | and conversions to other media types. 34 | 35 | "Work" shall mean the work of authorship, whether in Source or 36 | Object form, made available under the License, as indicated by a 37 | copyright notice that is included in or attached to the work 38 | (an example is provided in the Appendix below). 39 | 40 | "Derivative Works" shall mean any work, whether in Source or Object 41 | form, that is based on (or derived from) the Work and for which the 42 | editorial revisions, annotations, elaborations, or other modifications 43 | represent, as a whole, an original work of authorship. For the purposes 44 | of this License, Derivative Works shall not include works that remain 45 | separable from, or merely link (or bind by name) to the interfaces of, 46 | the Work and Derivative Works thereof. 47 | 48 | "Contribution" shall mean any work of authorship, including 49 | the original version of the Work and any modifications or additions 50 | to that Work or Derivative Works thereof, that is intentionally 51 | submitted to Licensor for inclusion in the Work by the copyright owner 52 | or by an individual or Legal Entity authorized to submit on behalf of 53 | the copyright owner. For the purposes of this definition, "submitted" 54 | means any form of electronic, verbal, or written communication sent 55 | to the Licensor or its representatives, including but not limited to 56 | communication on electronic mailing lists, source code control systems, 57 | and issue tracking systems that are managed by, or on behalf of, the 58 | Licensor for the purpose of discussing and improving the Work, but 59 | excluding communication that is conspicuously marked or otherwise 60 | designated in writing by the copyright owner as "Not a Contribution." 61 | 62 | "Contributor" shall mean Licensor and any individual or Legal Entity 63 | on behalf of whom a Contribution has been received by Licensor and 64 | subsequently incorporated within the Work. 65 | 66 | 2. Grant of Copyright License. Subject to the terms and conditions of 67 | this License, each Contributor hereby grants to You a perpetual, 68 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 69 | copyright license to reproduce, prepare Derivative Works of, 70 | publicly display, publicly perform, sublicense, and distribute the 71 | Work and such Derivative Works in Source or Object form. 72 | 73 | 3. Grant of Patent License. Subject to the terms and conditions of 74 | this License, each Contributor hereby grants to You a perpetual, 75 | worldwide, non-exclusive, no-charge, royalty-free, irrevocable 76 | (except as stated in this section) patent license to make, have made, 77 | use, offer to sell, sell, import, and otherwise transfer the Work, 78 | where such license applies only to those patent claims licensable 79 | by such Contributor that are necessarily infringed by their 80 | Contribution(s) alone or by combination of their Contribution(s) 81 | with the Work to which such Contribution(s) was submitted. If You 82 | institute patent litigation against any entity (including a 83 | cross-claim or counterclaim in a lawsuit) alleging that the Work 84 | or a Contribution incorporated within the Work constitutes direct 85 | or contributory patent infringement, then any patent licenses 86 | granted to You under this License for that Work shall terminate 87 | as of the date such litigation is filed. 88 | 89 | 4. Redistribution. You may reproduce and distribute copies of the 90 | Work or Derivative Works thereof in any medium, with or without 91 | modifications, and in Source or Object form, provided that You 92 | meet the following conditions: 93 | 94 | (a) You must give any other recipients of the Work or 95 | Derivative Works a copy of this License; and 96 | 97 | (b) You must cause any modified files to carry prominent notices 98 | stating that You changed the files; and 99 | 100 | (c) You must retain, in the Source form of any Derivative Works 101 | that You distribute, all copyright, patent, trademark, and 102 | attribution notices from the Source form of the Work, 103 | excluding those notices that do not pertain to any part of 104 | the Derivative Works; and 105 | 106 | (d) If the Work includes a "NOTICE" text file as part of its 107 | distribution, then any Derivative Works that You distribute must 108 | include a readable copy of the attribution notices contained 109 | within such NOTICE file, excluding those notices that do not 110 | pertain to any part of the Derivative Works, in at least one 111 | of the following places: within a NOTICE text file distributed 112 | as part of the Derivative Works; within the Source form or 113 | documentation, if provided along with the Derivative Works; or, 114 | within a display generated by the Derivative Works, if and 115 | wherever such third-party notices normally appear. The contents 116 | of the NOTICE file are for informational purposes only and 117 | do not modify the License. You may add Your own attribution 118 | notices within Derivative Works that You distribute, alongside 119 | or as an addendum to the NOTICE text from the Work, provided 120 | that such additional attribution notices cannot be construed 121 | as modifying the License. 122 | 123 | You may add Your own copyright statement to Your modifications and 124 | may provide additional or different license terms and conditions 125 | for use, reproduction, or distribution of Your modifications, or 126 | for any such Derivative Works as a whole, provided Your use, 127 | reproduction, and distribution of the Work otherwise complies with 128 | the conditions stated in this License. 129 | 130 | 5. Submission of Contributions. Unless You explicitly state otherwise, 131 | any Contribution intentionally submitted for inclusion in the Work 132 | by You to the Licensor shall be under the terms and conditions of 133 | this License, without any additional terms or conditions. 134 | Notwithstanding the above, nothing herein shall supersede or modify 135 | the terms of any separate license agreement you may have executed 136 | with Licensor regarding such Contributions. 137 | 138 | 6. Trademarks. This License does not grant permission to use the trade 139 | names, trademarks, service marks, or product names of the Licensor, 140 | except as required for reasonable and customary use in describing the 141 | origin of the Work and reproducing the content of the NOTICE file. 142 | 143 | 7. Disclaimer of Warranty. Unless required by applicable law or 144 | agreed to in writing, Licensor provides the Work (and each 145 | Contributor provides its Contributions) on an "AS IS" BASIS, 146 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or 147 | implied, including, without limitation, any warranties or conditions 148 | of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A 149 | PARTICULAR PURPOSE. You are solely responsible for determining the 150 | appropriateness of using or redistributing the Work and assume any 151 | risks associated with Your exercise of permissions under this License. 152 | 153 | 8. Limitation of Liability. In no event and under no legal theory, 154 | whether in tort (including negligence), contract, or otherwise, 155 | unless required by applicable law (such as deliberate and grossly 156 | negligent acts) or agreed to in writing, shall any Contributor be 157 | liable to You for damages, including any direct, indirect, special, 158 | incidental, or consequential damages of any character arising as a 159 | result of this License or out of the use or inability to use the 160 | Work (including but not limited to damages for loss of goodwill, 161 | work stoppage, computer failure or malfunction, or any and all 162 | other commercial damages or losses), even if such Contributor 163 | has been advised of the possibility of such damages. 164 | 165 | 9. Accepting Warranty or Additional Liability. While redistributing 166 | the Work or Derivative Works thereof, You may choose to offer, 167 | and charge a fee for, acceptance of support, warranty, indemnity, 168 | or other liability obligations and/or rights consistent with this 169 | License. However, in accepting such obligations, You may act only 170 | on Your own behalf and on Your sole responsibility, not on behalf 171 | of any other Contributor, and only if You agree to indemnify, 172 | defend, and hold each Contributor harmless for any liability 173 | incurred by, or claims asserted against, such Contributor by reason 174 | of your accepting any such warranty or additional liability. 175 | 176 | END OF TERMS AND CONDITIONS 177 | 178 | APPENDIX: How to apply the Apache License to your work. 179 | 180 | To apply the Apache License to your work, attach the following 181 | boilerplate notice, with the fields enclosed by brackets "[]" 182 | replaced with your own identifying information. (Don't include 183 | the brackets!) The text should be enclosed in the appropriate 184 | comment syntax for the file format. We also recommend that a 185 | file or class name and description of purpose be included on the 186 | same "printed page" as the copyright notice for easier 187 | identification within third-party archives. 188 | 189 | Copyright [yyyy] [name of copyright owner] 190 | 191 | Licensed under the Apache License, Version 2.0 (the "License"); 192 | you may not use this file except in compliance with the License. 193 | You may obtain a copy of the License at 194 | 195 | http://www.apache.org/licenses/LICENSE-2.0 196 | 197 | Unless required by applicable law or agreed to in writing, software 198 | distributed under the License is distributed on an "AS IS" BASIS, 199 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 200 | See the License for the specific language governing permissions and 201 | limitations under the License. 202 | -------------------------------------------------------------------------------- /LICENSE-MIT: -------------------------------------------------------------------------------- 1 | Copyright (c) 2015 2 | 3 | Permission is hereby granted, free of charge, to any 4 | person obtaining a copy of this software and associated 5 | documentation files (the "Software"), to deal in the 6 | Software without restriction, including without 7 | limitation the rights to use, copy, modify, merge, 8 | publish, distribute, sublicense, and/or sell copies of 9 | the Software, and to permit persons to whom the Software 10 | is furnished to do so, subject to the following 11 | conditions: 12 | 13 | The above copyright notice and this permission notice 14 | shall be included in all copies or substantial portions 15 | of the Software. 16 | 17 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF 18 | ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED 19 | TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 20 | PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT 21 | SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 22 | CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 23 | OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR 24 | IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 25 | DEALINGS IN THE SOFTWARE. 26 | -------------------------------------------------------------------------------- /README.rst: -------------------------------------------------------------------------------- 1 | 2 | defmac 3 | ====== 4 | 5 | Please read the `API documentation here`__ 6 | 7 | __ https://docs.rs/defmac 8 | 9 | |build_status|_ |crates|_ 10 | 11 | .. |build_status| image:: https://travis-ci.org/bluss/defmac.svg 12 | .. _build_status: https://travis-ci.org/bluss/defmac 13 | 14 | .. |crates| image:: http://meritbadge.herokuapp.com/defmac 15 | .. _crates: https://crates.io/crates/defmac 16 | 17 | Recent Changes 18 | -------------- 19 | 20 | - 0.2.1 21 | 22 | - Fix so that the macro can be used through its full path (like 23 | `defmac::defmac! { .. }` 24 | - Fix so that the macro can expand at module level 25 | 26 | - 0.2.0 27 | 28 | - New implementation that is general and variadic: defmac now supports 29 | making macros with arbitrarily many parameters! 30 | - Requires Rust 1.20 31 | 32 | - 0.1.3 33 | 34 | - Update docs with another example and a tip about syntactical variable 35 | capture. 36 | 37 | 38 | License 39 | ======= 40 | 41 | Dual-licensed to be compatible with the Rust project. 42 | 43 | Licensed under the Apache License, Version 2.0 44 | http://www.apache.org/licenses/LICENSE-2.0 or the MIT license 45 | http://opensource.org/licenses/MIT, at your 46 | option. This file may not be copied, modified, or distributed 47 | except according to those terms. 48 | 49 | 50 | -------------------------------------------------------------------------------- /src/lib.rs: -------------------------------------------------------------------------------- 1 | #![cfg_attr(not(test), no_std)] 2 | 3 | //! A macro to define lambda-like macros inline. 4 | //! 5 | //! Syntax: 6 | //! 7 | //! `defmac!(` *name* [ *pattern* [, *pattern* ... ]] `=>` *expression* `)` 8 | //! 9 | //! *name* is the name of the new macro, followed by 0 or more patterns 10 | //! separated by comma. A pattern can be just an argument name like `x` 11 | //! or a pattern like `ref value`, `(x, y)` etc. Note that there is no comma 12 | //! between the name and the first pattern. 13 | //! 14 | //! # Example 15 | //! 16 | //! ``` 17 | //! #[macro_use] extern crate defmac; 18 | //! 19 | //! fn main() { 20 | //! defmac!(mkvec iter => iter.into_iter().collect::>()); 21 | //! 22 | //! let v = mkvec!((0..10).map(|x| x * 2)); 23 | //! 24 | //! defmac!(repeat ref s, n => (0..n).map(|_| &s[..]).collect::()); 25 | //! 26 | //! let text = String::from("abc"); 27 | //! let s = repeat!(text, 10); 28 | //! let t = repeat!("-", s.len()); 29 | //! println!("{}", s); 30 | //! println!("{}", t); 31 | //! 32 | //! } 33 | //! ``` 34 | //! 35 | //! Did you know that macros can “capture” variables that they have in scope? 36 | //! The capture is by name instead of by reference, so we can use 37 | //! defmac where we cannot use closures. See the example below: 38 | //! 39 | //! ``` 40 | //! #[macro_use] extern crate defmac; 41 | //! 42 | //! fn main() { 43 | //! let mut result = Vec::new(); 44 | //! let mut sum = 0.; 45 | //! let input = "2 2 ^ 7 b ^"; 46 | //! 47 | //! defmac!(push elem => result.push(elem)); 48 | //! defmac!(double => *result.last_mut().unwrap() *= 2); 49 | //! 50 | //! for ch in input.chars() { 51 | //! match ch { 52 | //! '^' => double!(), 53 | //! '0'...'9' => push!(ch as u32 - '0' as u32), 54 | //! 'a'...'z' => push!(ch as u32 - 'a' as u32), 55 | //! _ => { } 56 | //! } 57 | //! } 58 | //! 59 | //! assert_eq!( 60 | //! result, 61 | //! vec![2, 4, 7, 2]); 62 | //! } 63 | //! ``` 64 | //! 65 | //! ## Rust Version 66 | //! 67 | //! This crate requires Rust 1.20 or later. 68 | 69 | /// A macro to define lambda-like macros inline. 70 | /// 71 | /// Syntax: 72 | /// 73 | /// `defmac!(` *name* [ *pattern* [, *pattern* ... ]] `=>` *expression* `)` 74 | /// 75 | /// *name* is the name of the new macro, followed by 0 or more patterns 76 | /// separated by comma. A pattern can be just an argument name like `x` 77 | /// or a pattern like `ref value`, `(x, y)` etc. 78 | /// 79 | /// Supports arbitrary many arguments. 80 | #[macro_export(local_inner_macros)] 81 | macro_rules! defmac { 82 | // nest matches final rule 83 | (@nest $name:ident ($dol:tt) => ( 84 | [$($arg:ident)*] $($result_body:tt)+) 85 | ) => { 86 | macro_rules! $name { 87 | ($($dol $arg : expr), *) => { 88 | $($result_body)+ 89 | } 90 | } 91 | }; 92 | 93 | // nest matches entry point and recursive rule 94 | (@nest $name:ident ($dol:tt) => ( 95 | [$($arg:ident)*] $($result_body:tt)+ 96 | ) 97 | $p1:pat $(, $p2:pat)* 98 | ) => { 99 | // `marg` is a hygienic macro argument name 100 | defmac!{@nest $name ($dol) => ( 101 | [marg $($arg)*] 102 | match {$dol marg} { $p1 => $($result_body)+ } 103 | ) 104 | $($p2),* } 105 | }; 106 | 107 | // reverse patterns before passing them on to @nest 108 | // reverse patterns final rule 109 | (@revpats [$($args:tt)*] [$($pr:pat),*]) => { 110 | defmac!{@nest $($args)* $($pr),*} 111 | }; 112 | 113 | // reverse patterns entry point and recursive rule 114 | (@revpats [$($args:tt)*] [$($pr:pat),*] $p1:pat $(, $p2:pat)*) => { 115 | defmac!{@revpats [$($args)*] [$p1 $(, $pr)*] $($p2),*} 116 | }; 117 | 118 | // entry point 119 | ($name:ident $($p1:pat),* => $result:expr) => { 120 | defmac!{@revpats [$name ($) => ([] $result)] [] $($p1),*} 121 | }; 122 | } 123 | 124 | 125 | #[cfg(test)] 126 | mod tests { 127 | #[test] 128 | fn it_works() { 129 | 130 | let value = "xyz"; 131 | 132 | defmac!(none => value); 133 | assert_eq!(none!(), "xyz"); 134 | 135 | defmac!(one x => x); 136 | assert_eq!(one!(2), 2); 137 | 138 | defmac!(two x, y => x + y); 139 | assert_eq!(two!(1., 2.), 3.); 140 | 141 | defmac!(three x, y, z => (x, y, z)); 142 | assert_eq!(three!(1, (2, 3), (4, 5, 6)), (1, (2, 3), (4, 5, 6))); 143 | 144 | defmac!(four w, x, y, z => (w + x, z, y)); 145 | assert_eq!(four!(3, 4, "a", "b"), (7, "b", "a")); 146 | 147 | defmac!(many a, b, c, d, e, f, g, h, i, j, k => (a, b + c, d + e + f, 148 | g + h + i + j + k)); 149 | assert_eq!(many!(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11), 150 | (1, 5, 15, 45)); 151 | } 152 | 153 | #[test] 154 | fn eval_order() { 155 | use std::cell::Cell; 156 | let v = Cell::new(0); 157 | let f = || { 158 | let n = v.get(); 159 | v.set(n + 1); 160 | n 161 | }; 162 | 163 | defmac!(two x, y => (x, y)); 164 | 165 | let result = two!(f(), f()); 166 | assert_eq!(result, (0, 1)); 167 | assert_eq!(f(), 2); 168 | } 169 | 170 | // Test expansion at module level 171 | defmac! { triple value => [value; 3] } 172 | 173 | #[test] 174 | fn module_macro() { 175 | assert_eq!(triple!(3), [3, 3, 3]); 176 | } 177 | } 178 | -------------------------------------------------------------------------------- /tests/cross_crate.rs: -------------------------------------------------------------------------------- 1 | 2 | #[test] 3 | fn full_path() { 4 | defmac::defmac! { len x => x.len() } 5 | 6 | assert_eq!(len!(&[1, 2]), 2); 7 | } 8 | --------------------------------------------------------------------------------