Hi,

I am pretty new to perl and need some ideas on how to build a regular expression to perform some substitutions, if at all possible. The input to the regular expression would be a string consisting of mathematical operations with variables '$<name>'. Basically, anytime the '$' keyword is found, replace with $sym{'$name'). Is this possible with regular expressions or do I need a parser?

eg. $x + $y = 7

$x * ($x - $y) + 10

$x + $x1 + $x2 ... = n

substitute with

$sym{'$x'} + $sym{'$y'} = 7

$sym{'$x'} * ($sym{'$x'} - $sym{'$y'}) + 10

$sym{'$x'} + $sym{'$x1'} + $sym{'$x2'} ... = n

This regular expression works for 1 letter variables, however it doesn't handle multiple vars. 

$ref =~ s/(\$\S)/\$sym->{'$1'}/g;

[download]

Thanks in advance, -P

In reply to Regular expression match and substitution by pip9ball

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