Increment every number in a string
Perl, 14 bytes

s/\d+/$&amp;+1/ge


Requires the -p switch, which I have counted as one byte.

Example run

$ perl -p &lt;(echo 's/\d+/$&amp;+1/ge') &lt;&lt;&lt; 'teststring134this 123test string54 100'
teststring135this 124test string55 101