4.6 Timing: the Timer structure

printTiming

Function

Structure

Shell.Timer

Type

val printTiming: {function: 'a -> 'b, name: string, outputter: string -> unit} -> 'a -> 'b
Syntax
printTiming {function=f, name=n, outputter=o} a -> g
Arguments

 
f
 A function.
 
n
 A string. 
 
a
 An argument for f.
 
o
 A function that prints out a string.

Values

 
g
 The return value for f applied to a.

Description
 This function returns the value of f applied to a, and as a side effect it prints the time taken to evaluate the expression.
Example
 Define the following function:
fun g x = let 
  fun f 0 _ = ()
   | f n m = (f m 0; f (n-1) m)
     in  f x x
  end;
 Below is an example of applying printTiming to g with an argument of 1000:
MLWorks>printTiming {function=g, 
                     name="hello",
                     outputter=print} 1000;
Time for hello : 0.54 (user: 0.49, system: 0.00, gc: 0.00)
val it : unit = ()
MLWorks>