mirror of https://github.com/rust-lang/rfcs
52 lines
1.4 KiB
Markdown
52 lines
1.4 KiB
Markdown
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# Guiding principles and rationale
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When deciding on style guidelines, the style team tried to be guided by the
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following principles (in rough priority order):
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* readability
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- scan-ability
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- avoiding misleading formatting
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- accessibility - readable and editable by users using the the widest
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variety of hardware, including non-visual accessibility interfaces
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- readability of code when quoted in rustc error messages
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* aesthetics
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- sense of 'beauty'
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- consistent with other languages/tools
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* specifics
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- compatibility with version control practices - preserving diffs,
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merge-friendliness, etc.
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- preventing right-ward drift
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- minimising vertical space
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* application
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- ease of manual application
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- ease of implementation (in Rustfmt, and in other tools/editors/code generators)
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- internal consistency
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- simplicity of formatting rules
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## Overarching guidelines
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Prefer block indent over visual indent. E.g.,
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```rust
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// Block indent
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a_function_call(
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foo,
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bar,
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);
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// Visual indent
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a_function_call(foo,
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bar);
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```
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This makes for smaller diffs (e.g., if `a_function_call` is renamed in the above
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example) and less rightward drift.
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Lists should have a trailing comma when followed by a newline, see the block
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indent example above. This choice makes moving code (e.g., by copy and paste)
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easier and makes smaller diffs.
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