String substitution in variable expansion #4427
Merged
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One of the variable expansion functions missing from #4287 was string substition, so I implemented it.
Motivating example:
The two parts following the variable name (pattern and replacement) need to be parsed separately with
processStopWords
, otherwise variable expansion could cause a/
in a variable referenced in the pattern to be interpreted as separator between patern and replacement. This means that the second/
is required (i.e.${foo/bar/}
to removebar
, compared to${foo/bar}
as accepted by various shells).On the positive side, wildcards and slashes in referenced variables are handled correctly (e.g.
PAT='*/'; REPL='.../'; ${FOO/$PAT/$REPL}
).