Using sed, how do I remove everything after the last dash (-) in a string?

So how do I turn

'blah-blah-123' or 'blah-blah-blah-123'

into

'blah-blah' or 'blah-blah-blah'

respectively?

--
mr. scary

Matches a hyphen, then any number of characters except a hyphen, until the end of the line. This means that only the last occurrence of the hyphen satisfies the string.

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Moin,

regular expressions are greedy (they catch the longest part of a line, which matches the pattern), so this will work:
Jan

P.S.: The only one exception from the "greedy behaviour" is the "?" quantifier in Perl compatible regular expressions (not supported by grep and sed).

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Thank you jan61. That works (your explanation is a nice bonus). I did, however, need to escape the parentheses.

You can use a simple parameter substitution instead of sed:

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Ha. Changed to the parameter substitution solution instead. Great solutions guys.

Awww, I almost mentioned the parameter substitution thing myself, but decided against it because the OP specifically asked for a sed solution. Since substitution requires the use of a variable, it's less convenient than sed when doing things like working with a text file, and since the purpose of the change wasn't mentioned I decided not to presume.

This is a good example of why questions like this really ought to be goal-centered: "how can I accomplish x", rather than process-centered: "how can I make y do x".


PS: If you use the -r switch in sed you don't need to escape the parentheses.

Moin,

did you use the -r option (extended regex)?

Jan