There are such expressions like:
name=="sometext"
value!=4
I would like to split such exp开发者_如何学Goressions with string separators like "==" and "!=" and keep these separators, so result would be:
name=="sometext" -> [name] [==] ["sometext"]
value!=4 -> [value] [!=] [4]
How can it be done with Boost or some other library?
With boost I would use this simple regex :
(.*?)(==|!=)(.*)
Edit : provided that the expression is a string.
Edit 2 : explanation of the regex
// (.*?)(==|!=)(.*)
//
// Match the regular expression below and capture its match into backreference number 1 «(.*?)»
// Match any single character that is not a line break character «.*?»
// Between zero and unlimited times, as few times as possible, expanding as needed (lazy) «*?»
// Match the regular expression below and capture its match into backreference number 2 «(==|!=)»
// Match either the regular expression below (attempting the next alternative only if this one fails) «==»
// Match the characters “==” literally «==»
// Or match regular expression number 2 below (the entire group fails if this one fails to match) «!=»
// Match the characters “!=” literally «!=»
// Match the regular expression below and capture its match into backreference number 3 «(.*)»
// Match any single character that is not a line break character «.*»
// Between zero and unlimited times, as many times as possible, giving back as needed (greedy) «*»
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