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isnumber [2006/08/01 03:45] (current) – created - external edit 127.0.0.1
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 +# $EPIC: isnumber.txt,v 1.2 2006/08/01 03:40:36 sthalik Exp $
 +======Synopsis:======
 +$__isnumber__(<text>) \\ 
 +$__isnumber__(b<base-num> <text>) \\
 +$__isnumber__(<text> b<base-num>)
 +
 +======Technical:======
 +   * The <base-num> argument may either be the first or second word, but in either case must be prefixed with the literal 'b' character.
 +   * The <text> argument may either be the first or second word, but in either case must NOT be prefixed with the literal 'b' character.
 +   * If the <base-num> argument is not specified, the default value is 0.
 +   * If <base-num> is 0, the number base is auto-detected.
 +   * <text> is taken to be a string containing an integer value, a decimal point ('.' -- sorry), and another integer value; comprised of digits which are legal in the indicated base.
 +   * If a decimal point is used and the <base-num> is 0, then the integer value after the decimal point must be in base 10 and will not be auto-detected.
 +   * The return value is 1 if <text> is a valid number in the indicated base, and 0 if <text> is not a valid number in the indicated base.
 +
 +======Practical:======
 +Wow.  That's complicated.  This function (believe it or not) just tells
 +you whether or not <text> is a number.  You can specify a number base
 +(such as b8, or b16) to see if <text> is a number in a base other than 
 +base 10.  This is neccesary if you want to octal or hexidecmial numbers
 +for validity.
 +
 +======Returns:======
 +1 if <text> is a valid number of base <base-num>; 0 if not.
 +
 +======Examples:======
 +<file>
 +$isnumber(10)             returns 1
 +$isnumber(hello)          returns 0
 +$isnumber(0xdeadbeef)     returns 1  (all hex digits!)
 +$isnumber(b8 0xdeadbeef)  returns 0  (not an octal number!)
 +$isnumber(b8 07f932)      returns 0  (9 is not an octal digit!)
 +$isnumber(3.4)            returns 1
 +$isnumber(b16 a.f)        returns 1
 +$isnumber(a.f)            returns 0  (hex digits invalid without 0x)
 +$isnumber(0xa.0)          returns 1
 +$isnumber(b16 a.f)        returns 1  (hex digits valid with b16)
 +</file>
  
isnumber.txt · Last modified: 2006/08/01 03:45 by 127.0.0.1