Re^2: YAML::XS perl/regexp (?u:(?u:

It would be possible to store a regex as a sequence and use the same tag for it:

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re1: !!perl/regexp (?^usi:pattern)
re2: !!perl/regexp [ pattern, isu ]
[download]

For perl 5.8 the old behaviour could be used. This could be done for YAML and YAML::XS. Possibly also for YAML::Syck, which has the same problem, but I would have to ask Todd, the maintainer.

Comment on Re^2: YAML::XS perl/regexp (?u:(?u: Download Code

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Re^3: YAML::XS perl/regexp (?u:(?u: by ikegami (Patriarch) on Dec 19, 2017 at 19:29 UTC
You can add understanding of `!!perl/regexp [ pattern, isu ]` at any time, but backwards compatibility requires making the generation of that an option. Eventually, once support has been established, it could default to the new method.	[reply] [d/l]
Re^4: YAML::XS perl/regexp (?u:(?u: by tinita (Parson) on Dec 19, 2017 at 21:17 UTC
Another possibility would be to continue just using a string. Check with `regexp_pattern()`, if there are any flags (ignoring `u`), just store the stringified regex, otherwise store the pattern itself. This would still lead to unnecessary `(?:...)` but it wouldn't grow in roundtrips. Have been looking into universal.c how regexp_pattern() is implemented. At the moment it's too much magic for me to understand.	[reply] [d/l] [select]
Re^5: YAML::XS perl/regexp (?u:(?u: by ikegami (Patriarch) on Dec 20, 2017 at 15:57 UTC
I don't know what you mean by "check with `regexp_pattern()`, if there are any flags (ignoring `u`)". Do you mean "check if the results of `( regexp_pattern(qr/$pat/) )[1]` contains anything but `u`"? It never will (unless you use `use re "/..."`, which would be bad here).	[reply] [d/l] [select]
Re^6: YAML::XS perl/regexp (?u:(?u: by tinita (Parson) on Dec 20, 2017 at 23:05 UTC
Re^7: YAML::XS perl/regexp (?u:(?u: by ikegami (Patriarch) on Dec 21, 2017 at 21:55 UTC