regex - Find location of $ in string -


based on advice here: find location of character in string, tried this: 

> gregexpr(pattern ='$',"data.frame.name$variable.name") [[1]] [1] 30 attr(,"match.length") [1] 0 attr(,"usebytes") [1] true

but didn't work; note: 

> nchar("data.frame.name$variable.name") [1] 29

how find location of $ in string?

the problem $ end-of-string marker in regex. try instead:

> gregexpr(pattern ='\\$',"data.frame.name$variable.name") [[1]] [1] 16 attr(,"match.length") [1] 1 attr(,"usebytes") [1] true

... gives right answer - i.e. 16.


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