Re^5: Do nothing? or Do something important in a very obscure way?

Actually, what x{0} says is "succeed if there are zero x'es here". And that's always true, because we can always match none of something, even in an empty string. So basically, x{0} is a NOP, and so is x??: and x*?:.

Makeshifts last the longest.

Comment on Re^5: Do nothing? or Do something important in a very obscure way?

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Re: Re^5: Do nothing? or Do something important in a very obscure way? by BrowserUk (Patriarch) on Aug 23, 2002 at 19:23 UTC
Actually, that's exactly what I thought it meant, hence the "Do nothing?" in the title. I remember the days when I used to be obliged to put blocks of NOP's into my assembler subroutines (we used a ratio of 1::20 active instructions) to allow space for remedial patching of the executable, but I couldn't see why you would add them to a regex! What's this about a "crooked mitre"? I'm good at woodwork!	[reply]
Re^7: Do nothing? or Do something important in a very obscure way? by Aristotle (Chancellor) on Aug 23, 2002 at 23:31 UTC
There is no reason to be adding them to a regex. It is simply due to the way the double colon works that postfixing it to a nongreedy match turns the match into a NOP, which is what TheDamian was mentioning in the Exegesis. Makeshifts last the longest.	[reply]