Warn about unused return values. #677
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| char const* text = R"( | ||
| contract test { | ||
| function f() { | ||
| address(0x12).send(1); |
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actually really quick, just trying to understand this bit. Why does this one throw a warning?
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Because the return value of send is ignored.
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Part of me says this is smart, but then the other part of me says this can get annoying when it comes to void contracts.
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@VoR0220 Do void contracts ignore return values? (BTW, what's a void contract?)
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Should have said void contract function. That is my terminology for a contract function that doesn't return a value. Although with the send...yeah you should be checking to make sure it happened.
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address(0x12).send(1); this call's return value is ignored. this is the source of the warning, not f().
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right, but that should be irrelevant if it's inside function f's scope.
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Sorry if what I'm about to say is obvious or wrong. Bear with me as I'm learning lots at once. After a quick review of the code (disclaimer: I never learned C/C++ very well), it looks like this is part of the visitor pattern. If that's the case, then it looks like this code is being run on every single ExpressionStatement in the AST. So I think that means scope is irrelevant.
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right, and I'm saying scope should be relevant.
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actually...I just realized I'm wrong. This is good to merge.
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Relaxed the warning to only be fired only for the low-level functions call, send, callcode and delegatecall. |
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Much appreciated. |
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much appreciated. Let me take another look. |
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