No HKT or type classes, so each structure in F# has its own map implementation.
I'm not sure why it doesn't work in Haskell tbh. Possibilities are that (+) is not recognized as integer addition. Or that the negative sign on -1 is parsed as a function.
Ah. I wonder why -1 requires parens. I also thought that you can turn an inline operator into a regular function by putting parens around it. (And vice versa with back ticks). I guess I should do my own Haskell homework instead of asking here. :)
If I remember accurately it is because anything that is not a value in haskell is a function.
So without the parentheses it can't know if -1 means the function - applied to some other value and the number one like1-1( function - applied to 1 and 1 ) or the value -1, so the way they solved it is to have it be the function, therefore you would be missing an argument or you would be passning a wrong type.
When you want a value you would have to use (-1) so then it knows that you trully mean the value -1.
PS: This is my first comment I hope I didn't come out sounding a but too "know it all" or trying to sound smart, I just wanted to explain it the best I can.
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Huh, this works verbatim in F#.
No HKT or type classes, so each structure in F# has its own
mapimplementation.I'm not sure why it doesn't work in Haskell tbh. Possibilities are that
(+)is not recognized as integer addition. Or that the negative sign on-1is parsed as a function.Indeed, Haskell is picky.
map (+ (-1)) [-10..0]
is a working solution.
Also there is another one, specifically to address the problem with the minus sign:
map (subtract 1) [-10..0]
Ah. I wonder why -1 requires parens. I also thought that you can turn an inline operator into a regular function by putting parens around it. (And vice versa with back ticks). I guess I should do my own Haskell homework instead of asking here. :)
If I remember accurately it is because anything that is not a value in haskell is a function.
So without the parentheses it can't know if
-1means the function-applied to some other value and the number one like1-1( function-applied to 1 and 1 ) or the value -1, so the way they solved it is to have it be the function, therefore you would be missing an argument or you would be passning a wrong type.When you want a value you would have to use
(-1)so then it knows that you trully mean the value -1.PS: This is my first comment I hope I didn't come out sounding a but too "know it all" or trying to sound smart, I just wanted to explain it the best I can.