Add some comments about how quote_each_token works.
#211
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I didn't understand how this code worked until I used `trace_macros` on an example and saw some expansions. This commit contains the comments I wish had been present.
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I updated the comment about performance -- the tt muncher is quadratic, this implementation is linear, but this implementation has higher constant factors and so is slower for short inputs. (I did some microbenchmarking to determine this.) |
dtolnay
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Mar 25, 2022
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| // The parentheses around the middle tt aren't necessary, but they make the | ||
| // macro definitions easier to read. |
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This part isn't right. I don't know how we would correctly drop the first 3 and last 3 quote_token_with_context calls without bracketing the middle token to make it unable to collide with the padding token (@).
I'll fix this in a followup PR.
dtolnay
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Mar 25, 2022
Touch up comments from PR #211
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I didn't understand how this code worked until I used
trace_macrosonan example and saw some expansions. This commit contains the comments I
wish had been present.