NEW 225878
Replace non-ownership transfer requiring uses of WTF::Function to use WTF::ScopeLambda to avoid allocation of WTF::Function 
https://bugs.webkit.org/show_bug.cgi?id=225878
Summary Replace non-ownership transfer requiring uses of WTF::Function to use WTF::Sc...
Sam Weinig
Reported 2021-05-17 10:28:13 PDT
Using WTF::Function (or std::function) in cases where are using a functor as an abstraction to allow scope customization, iteration or predicate functions is wasteful. We should instead be using the non-allocating WTF::ScopedLambda. Some examples in WebCore are: - the traverseSubresources() functions on various classes. - readURLsFromPasteboardAsString() in DataTransfer.cpp - Document::forEachMediaElement() - etc.
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Add attachment proposed patch, testcase, etc.
Darin Adler
Comment 1 2021-05-17 23:34:09 PDT
Grep for "const Function&" perhaps to find a lot of these?
Darin Adler
Comment 2 2021-05-17 23:34:31 PDT
Is there a reason this class needs to be named "lambda" and not "function"?
Sam Weinig
Comment 3 2021-05-18 16:23:09 PDT
(In reply to Darin Adler from comment #2) > Is there a reason this class needs to be named "lambda" and not "function"? The patch that added it doesn't give much justification: https://trac.webkit.org/changeset/191705/webkit Phil, any reason you chose "lambda" over "function" here?
Radar WebKit Bug Importer
Comment 4 2021-05-24 10:29:20 PDT
<rdar://problem/78407384>
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