Re: [OT] Thoughts on Ruby's new absent operator?

[LanX]

Well, here "my thoughts"

How do I post a question effectively?

my problems:

• First of all this should be a meditation
• Then you are linking to another discussion instead to a definition.
• After digging out the article I'm confronted with a lot of rubyisms I don't understand.

Why don't you try to explain to us the advantages of this construct over negativ look (ahead|behinds) in (pseudo) Perl code?

That's the way to initiate a decent discussion here.

[perlancar]

I admit spending too little time on the post, while waiting to go into a class and on a rather fickle wifi connection, so I guess I kind of deserve your reply. That said: 1) I did consider Meditations, but picked Seekers of Perl Wisdom instead; 2) I assume at least some of the monks here are fans of regular expressions and have read about the absent operator, so I need not present much introductory materials.

I have no strong opinion yet on the feature, perhaps will only do so after finding some practical use-case for it and seeing its performance characteristics.

[LanX]

Sorry but the sources I found are frustratingly obscure, and installing the latest ruby to understand a badly documented experimental feature is not an option.

[Anonymous Monk]

Was it really that hard to follow?

"The negative look-behind essentially looks to see if the specified expression is present and then fails if so. The absence operator, however, ensures that anything that isn’t the specified expression will match."