Q&A
| Q1: | The pattern /W(w)+W/ doesn't seem to match all the words on the line, just the ones in the middle. Why? |
| A1: | You're looking for word characters surrounded by nonword characters. The first word of the line—assuming it starts at the beginning of the line—doesn't have a nonword character in front of it. It doesn't have a character in front of it at all. |
| Q2: | What's the difference between m// and //? I don't get it. |
| A2: | There's almost no difference at all. The only difference is that if you decide to specify a pattern delimiter other than /, you can do so only if you precede the pattern with an m—for example, m!pattern!. |
| Q3: | I'm trying to verify that the user typed a number, but /d*/ doesn't seem to work. It always returns true! |
| A3: | It returns true because a pattern using only the * quantifier always succeeds. It might match zero occurrences of d, or it might match 2 or 100 or 1,000. Using /d+/ ensures that you have at least one digit. |
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