Hyphenation Solution - Programming Languages

Here's a pretty good answer.

We definitely want to match single words and then you can possibly have 1 hypen

and then you can have more letters if you like.

This regular expression definitely matches well-liked.

It also matches html--maybe the h, t, and m will match the first part,

and the l will match the second part.

It definitely rejects a-b-c and a--b.

However, 1 problem with this regular expression is that it does not accept

single letter words like "a" or "i".

To see why, just look at these 2 plus signs.

This requires 1 or more letters here and 1 or more letters there,

That's at least 2 letters.

We might be tempted to fix it up by making 1 of these a star,

but now we mistakenly accept things like just "-a".

No letters here, the hypen, and then some more letters--

well, that didn't work.

What if I try to make the other one a star?

Well, dual problem--now we'll mistakenly accept things like "a-".

Well, this is a bit of a challenge.

What we really want is for this hypen and the second word to be grouped together,

and either they're both there or they're not.

It's as if I really want this question mark to apply to both the hyphen

and also the [a - z]+.

We don't know how to do that yet, but you'll get a chance after we've learned how

to fix this up in the homework.