File concatenation principle #6031
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josh11b
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Sep 9, 2025
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| Carbon uses syntax to denote the start of a library or package, which functions | ||
| at the top of a file or in the middle of a file in the same way. Language rules |
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This isn't really true. You are only allowed to put the header lines before other declarations, and only once. I think the idea should be closer to saying that there should be a purely mechanical process for combining two files.
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| code in either file. It will be required to order the concatenation so that | ||
| dependencies are ordered first, in order to maintain the information |
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I think it may be worth saying a bit more about imports. Can adding imports lead to ambiguities that create diagnostics?
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| accumulation principle. There is always an ordering that allows any Carbon | ||
| project to be fully concatenated into a single Carbon source file and thus built | ||
| with a single compiler invocation. |
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I don't think we have a plan to support multiple packages in a single file.
josh11b
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Sep 9, 2025
| recreate and distribute a bug repro or to build a piece of C++ code in an | ||
| environment without the requirement of a build system. This allows code taken | ||
| from any build environment to be easily compiled by a developer in any other | ||
| environment, through a single compiler invocation. |
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Maybe also mention minimization?
Co-authored-by: josh11b <[email protected]>
Co-authored-by: josh11b <[email protected]>
Co-authored-by: Carbon Infra Bot <[email protected]>
Co-authored-by: Carbon Infra Bot <[email protected]>
josh11b
reviewed
Sep 9, 2025
| project to be fully concatenated into a single Carbon source file and thus built | ||
| with a single compiler invocation. | ||
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| ## Applications of these principles |
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Could you add something about the example that led us to forming the principle?
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We propose a principle that it's always possible to concat together Carbon source files without changing the meaning of or diagnostics applied to the code.