1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
\DOC do
\TYPE {$do : (* -> void)}
\SYNOPSIS
Evaluates an expression for its side-effects.
\DESCRIBE
The function {do} evaluates its argument (presumably for its side-effects)
and returns the value {(): void}.
\FAILURE
Fails iff the evaluation of its argument fails.
\EXAMPLE
The following shows how an assignment can be evaluated for its
side-effects:
{
#letref x = 1;;
x = 1 : int
#x := x + 1;;
2 : int
#do (x := x + 1);;
() : void
#x := x + 1;;
4 : int
}
\COMMENTS
The use of {do} as if it were a normal ML function should not be confused with
its role as a syntactic construct in a while loop. For example, following on
from the above example, consider the following:
{
#while x > 0 do do (x := x - 1);;
() : void
#x;;
0 : int
}
\noindent In the above, the first {do} is part of the {while} loop, whereas the
second is function-like.
\ENDDOC
|
