Is there a way to partially apply getLine?

Question

Is there a way to partially apply getLine to writeFile or a similar function (for file naming purposes)? I want to do something like this:

main = writeFile ??? . computeSomething =<< somethingElse

??? should be a line entered by the user to name the output file but I have no idea what to insert for ???. I tried inserting =<< getLine and similar snippets but nothing worked for me.

Is it possible to achieve this without using do-notation in a readable way?

`writeFile` has two arguments, a path and a string. We get the path from `getLine`, but what's the string to write? — András Kovács, Feb 14 '15 at 14:13
@AndrásKovács The string is what is returned by ``computeSomething``. — ThreeFx, Feb 14 '15 at 14:14
@Zeta *facepalm* Yes, thank you. This is a sign I have to take a break ;) Do you want to answer it or should I delete this question? — ThreeFx, Feb 14 '15 at 14:19

score 2 · Accepted Answer · answered Feb 14 '15 at 14:49

2

You can use flip to flip the order of arguments:

getLine >>= flip writeFile computeSomething

The tool pointfree is helpful if you want to eta-reduce a function.

answered Feb 14 '15 at 14:49

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Is there a way to partially apply getLine?

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