Generating all string possibilities with wildcard characters? (code golf-based)

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1

I ran into this code golf problem on StackExchange. The premise is that you take in a short string with some wildcard characters (*) and return all of the possible variations of that string, replacing the wildcards with each letter of the alphabet. Here’s an example the original question gives:

Input:

*e*c*m*

Output:

aeacama
aeacamb
...
...
...
welcome
...
...
zezczmz

After working through some initial attempts, I realized I actually have no idea how I would solve this effectively! :sweat_smile: I’m not even interested in golfing it anymore, per se, I’m mostly looking to expand my horizons a bit.

I’d love to see some Julian approaches to this, if anyone has any—I’m especially intrigued by things like the functional Haskell solution, since I know Julia leans more functional than some other languages, but I’d love to see anything people can come up with. Could anyone demonstrate some good ways to tackle this problem?

2

Not very golfed but here is something to start off with:

f(s) = '*' in s ? reduce(vcat, (f.(s) for s in replace.(s, "*" .=> 'a':'z', count=1))) : [s]
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