Lazy regex with OR

Question

I have strings of the form:

greengrocerabc
sandwichcba
oscardcba

I'd like to lazily match abc, abcd and abcde, so I can get the first component. So something like

sub("^(.+)(abc|cba|dcba)", "\\1", "oscardcba") => "oscar"

However, regexp OR greedy matches cba and I get oscard

How can I lazy match this OR? The language is R, but it can can act like grep or perl.

Felix Kling · Accepted Answer · 2011-08-16 17:33:50Z

4

Then make the quantifier non-greedy:

^(.+?)(abc|cba|dcba)

This way, the capture group will only contain the shortest possible match (which will not include abc, cba or dcba).

Further reading:

answered Aug 16, 2011 at 17:28

Felix Kling

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