Talk:cpp/regex/ecmascript
[edit] Usefulness
Currently we're already linking to the ECMAScript spec from cpp/regex/syntax_option_type (granted, that could use being more visible). I believe pages on each supported regex syntax could be useful if they
- correct and complete (as written, this page is incomplete: it's missing all the locale-sensitive classes supported by C++ in ECMAScript mode)
- have small examples or at least prose to illustrate and explain different grammar (otherwise it's no better than following a link to the standard)
--Cubbi (talk) 08:42, 21 October 2013 (PDT)
PS: I suspect that this page, as written, was strongly influenced by http://www.cplusplus.com/reference/regex/ECMAScript/ or whatever its author used as the source -- it follows exact same layout for the part it covers. It would look better if this wiki followed either the standard or boost.regex, or something of its own --Cubbi (talk) 11:29, 21 October 2013 (PDT)
- I agree, in its current form the page is not much useful. However, there's indeed not much to lose if we have a well documented and consistent documentation of all supported syntaxes. --P12 04:53, 23 October 2013 (PDT)
[edit] Example
This example:
show_matches("zaacbbbcac", "(z)((a+)?(b+)?(c))*");
Is currently confusing because the default compiler gcc 9.2 gets the wrong answer:
input=[zaacbbbcac], regex=[(z)((a+)?(b+)?(c))*]: prefix=[] m[0]=[zaacbbbcac] m[1]=[z] m[2]=[ac] m[3]=[a] m[4]=[bbb] m[5]=[c] suffix=[]
Clang 5.0 produces the correct answer:
input=[zaacbbbcac], regex=[(z)((a+)?(b+)?(c))*]: prefix=[] m[0]=[zaacbbbcac] m[1]=[z] m[2]=[ac] m[3]=[a] m[4]=[] m[5]=[c] suffix=[]
(cf. m[4])
73.252.173.18 23:40, 20 December 2019 (PST)
