Difference between revisions of "User:Lenny222/Haskell explained to the busy"

Revision as of 15:09, 29 September 2009

You have heard about Haskell but don't have the time to find out what it is?

I hope this page is for you.

Question	Answer
What is Haskell?	Haskell is a purely functional, lazy, statically typed programming language
What is a purely functional programming language?	TODO
What is a lazy programming language?	TODO
What is a statically typed programming language?	TODO
Why the name "Haskell"?	Haskell is named after the American mathematician Haskell Curry

Question	Answer
What is the meaning of the dollar sign "$"?	"$" is a way to compose functions, but avoid typing too many brackets. For example: foo x = h (g (f x)) is the same as foo x = h $ g $ f x
What is the meaning of the dot "."?	"." is used to compose functions in point-free style, similar to "$". For example: foo x = h $ g $ f x is the same as foo = h . g . f
What is point-free style?	Point-free style is a way to define functions solely as a composition of other functions, leaving arguments in the definition out. For example: takeFive x = take 5 x is the same as takeFive = take 5 in point-free style.
What is the meaning of "data"?	TODO
What is the meaning of "newtype"?	TODO
What is the meaning of "type"?	TODO

Question	Answer
What is a Monad?	TODO
What is the meaning of "forall"?	TODO

@@ Line 33: / Line 33: @@
 |-
 |What is the meaning of the '''dollar''' sign "'''$'''"?
-|"$" is a way to avoid typing too many brackets.
+|"$" is a way to compose functions, but avoid typing too many brackets.
 For example:
 <haskell>foo x = h (g (f x))</haskell>
 is the same as
 <haskell>foo x = h $ g $ f x</haskell>
+|-
+|What is the meaning of the '''dot''' "'''.'''"?
+|"." is used to compose functions in point-free style, similar to "$".
+For example:
+<haskell>foo x = h $ g $ f x</haskell>
+is the same as
+<haskell>foo = h . g . f</haskell>
 |-
 |What is '''point-free style'''?
@@ Line 46: / Line 53: @@
 <haskell>takeFive = take 5</haskell>
 in point-free style.
-|-
-|What is the meaning of the '''dot''' "'''.'''"?
-|"." is used to compose functions in point-free style, similar to "$".
-For example:
-<haskell>foo x = h $ g $ f x</haskell>
-is the same as
-<haskell>foo = h . g . f</haskell>
 |-
 |What is the meaning of "'''data'''"?