a C-like double-quoted string "(\\.|[^\\"])*"

adl / hoaf

Hanoi Omega-Automata Format

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a C-like double-quoted string "(\\.|[^\\"])*" #9

Closed strejcek closed 10 years ago

strejcek commented 10 years ago

Can you please explain the regular expression. I don't get the double backslashes and the meaning of .|[^"] - it seems to me that this matches any character, or not?

adl commented 10 years ago

\\. matches a backslash followed by any character,
[^\\"] matches any character that is not a backslash or double-quote,
(\\.|[^\\"])* match a sequence of any combination of the above two,
"(\\.|[^\\"])*" simply requires double-quotes around that.

For a rationale, consider a string with escaped double-quotes such as "hello \"world\"\n".

strejcek commented 10 years ago

I get it. Thanks for explanation. (I'm not skilled enough in this backslash gymnastics.)