ParserBase: avoid copying around currentLiteral#15741
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clonker
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Jan 20, 2025
| { | ||
| expectToken(Token::StringLiteral, false); | ||
| auto const name = currentLiteral(); | ||
| std::string const name{currentLiteral()}; |
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Here storing an explicit copy is required as we advance before returning from the function.
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Since this is an issue, it may be worthwhile to document the lifetime of the string_view in the header (i.e. state that advance invalidates it there)?
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r0qs
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nikola-matic
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This is something that I randomly stumbled upon when looking at #15712.
The function
ParserBase::currentLiteral()is called very frequently, in particular also in a lookup-style (e.g.,m_dialect.findBuiltin(currentLiteral())). Currently, each invocation takes a full copy of the string value of whatever the scanner is pointing to.