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This allows whitespace to be inspected in some special cases.
Define the combination of head/kind/flags functions as a more formal API - many syntax nodes and token types need these. On top of this we can define various predicates such as `is_trivia` in one place rather than having multiple definitions of these functions.
The token_type() function no longer exists
* Use Ref to avoid triggering boxing of captures via closure variable assignment. * Use let blocks for temporary ParseState transitions to avoid some closures.
This change implements a fast-path for token lookahead in peek() and increases the size of the lookahead buffer to make this more efficient.
Manually track an index into the lookahead buffer to avoid buffer resizing. (Julia's builtin array actually uses the same strategy to avoid shuffling elements in popfront!(). But an extra layer here can help as we know more about the data access.)
Some inbounds annotations in the `peek()` hot code paths seem to provide a few percent improvement (maybe 5%)?
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Overall this seems to boost the parser's speed by around 40% :-) |
c42f
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…-token-lookahead Optimization and cleanup in parse stream
topolarity
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…-token-lookahead Optimization and cleanup in parse stream
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This is a series of cleanup/optimization commits which
ParseStreamEMPTY_TOKENin Tokenize