Lazily evaluate const fns #15211
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Lazily evaluate const fns #15211
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This should definitely not be changed in this manner. Just because the function call could be evaluated by the compiler doesn't mean it is, nor does it mean the expression is cheap to compute. It does happen to be a good indicator that the call isn't expensive hence why it currently suggests not changing anything if it is eagerly evaluated. |
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I agree with @Jarcho here: a |
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As discussed in #15122 (comment), try converting eagerly evaluated const fn's into lazy ones.
This seems to have some undesired effects, so I'm not sure if this should be merged. Namely clippy would now suggest lazily evaluating cheap functions like String::new() or Duration::from_seconds({argument known at compile-time}).