C:\>perl -pe"if($_eq'baz-123'){print'bar=2'}" old > new
String found where operator expected at -e line 1, near "123'){print'"
        (Missing operator before '){print'?)
Bareword found where operator expected at -e line 1, near "'){print'ba
+r"
        (Missing operator before bar?)
String found where operator expected at -e line 1, at end of line
        (Missing semicolon on previous line?)
syntax error at -e line 1, near "123'){print'"
Can't find string terminator "'" anywhere before EOF at -e line 1.
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Why not use the -i command line option?
Since baz is the only constant, it should be =~ /baz/ and not eq
print 'bar=2' wtf is the newline?
Thanks for broken code that would not do the job even if it worked