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
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
NAME
test - whether a value is deemed to be true or false
SYNOPSIS
test(x)
TYPES
x any
return 0 or 1
DESCRIPTION
This function returns 1 or 0 according as x tests as "true" or "false".
Conditions under which a value x is considered to be false are:
Numbers (real or complex): x is zero
String: x == ""
Matrix: every component of x tests as false
List: every element of x tests as false
Association: x has no element
File: x is not open
Null: always
Object of type xx: if xx_test has been defined, xx_test(x)
returns zero; if xx_test has not been defined,
every element of x tests as false.
Error-value or other types: never
EXAMPLE
; print test(27), test(0), test("abc"), test("")
1 0 1 0
; print test(mat[3] = {1,,2}), test(mat[2][2])
1 0
; A = list(0, 2, 0)
; print test(A), test(pop(A)), test(A), test(pop(A)), test(A)
1 0 1 1 0
LIMITS
none
LINK LIBRARY
none
SEE ALSO
isassoc, isfile, isident, isnum, isint, islist, ismat, isnull, isobj,
isreal, isstr, issimple, istype
## Copyright (C) 1999-2006 Landon Curt Noll
##
## Calc is open software; you can redistribute it and/or modify it under
## the terms of the version 2.1 of the GNU Lesser General Public License
## as published by the Free Software Foundation.
##
## Calc is distributed in the hope that it will be useful, but WITHOUT
## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
## or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
## Public License for more details.
##
## A copy of version 2.1 of the GNU Lesser General Public License is
## distributed with calc under the filename COPYING-LGPL. You should have
## received a copy with calc; if not, write to Free Software Foundation, Inc.
## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
##
## Under source code control: 1996/07/11 01:05:13
## File existed as early as: 1996
##
## chongo <was here> /\oo/\ http://www.isthe.com/chongo/
## Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
|
