| defining a named function with explicitly named arguments |
incrementInteger :: Int -> Int
incrementInteger n = n + 1
|
incrementInteger[n_Integer] := n + 1;
|
|
| defining a named function with lambda expression |
incrementInteger :: Int -> Int
incrementInteger = \n -> n + 1
|
incrementInteger = Function[{n}, n + 1];
|
|
| defining a function with a function name as one of the
arguments |
Prelude> increment = \x -> x+1
Prelude> double = \x -> 2*x
Prelude> thenDouble someFunc = double . someFunc
Prelude> thenDouble increment 3
8
|
In[1]:= double = Function[x, 2x];
increment = Function[x, x + 1];
thenDouble[someFunc_] := Composition[double, someFunc];
In[4]:= thenDouble[increment]
Out[4]= Function[x, 2 x]@Function[x, x + 1]
In[5]:= (thenDouble[increment])[3]
Out[5]= 8
|
|
| defining a function with locally definded intermediate
functions |
Prelude> :{
Prelude> myFunc1 x =
Prelude> let y = sin x
Prelude> in cos y
Prelude> :}
Prelude> myFunc1 pi
1.0
Prelude> :{
Prelude> myFunc2 x =
Prelude> cos y
Prelude> where
Prelude> y = sin x
Prelude> :}
Prelude> myFunc2 pi
1.0
|
In[1]:= myFunc[x_]:=With[{f=Sin[x]},Cos[f]]
myFunc[Pi]
Out[2]= 1
|
Alternatively, instead of using With
(for symbolic replacement),
use Module (for lexical scoping) or Block
(for dynamic scoping). |