to_integer
| Definition: | integer res = to_integer(string s, integer def_value = 0, base = 10) |
| Description: |
Converts a string representation of a decimal integer into an actual integer.
s: A string such as "42". def_value: The value to return on failure. base: The number base to use (2..36). Returns the integer equivalent of s, or def_value. |
| pwa/p2js: | Supported. |
| Comments: |
This is, quite deliberately, just about the simplest possible implementation of such a function.
Use to_number() to deal with values exceeding an integer, fractions, exponents, underscores, etc. By default to_integer(s) returns 0 for both "0" and "abc". To sidestep that kind of potential confusion there is a sister function, bool res = is_integer(string s[,base=10]), which obviously annihilates any such ambiguity. Note that to_integer("-1073741824") fails/returns def_value after having set sgn to -1 but then finding "1073741824" is not an integer (only just), and also that is_integer() actually depends on that behaviour (of to_integer), and likewise yields false for "-1073741824". (Of course that "-1073741824" is replaced with "-4611686018427387904" on 64bit.) Note that when base is 16 it is permitted for s to begin with ["+"/"-"] "#" or "0x"/"0X", however there is no such handling for "0b", "0o", "0t", or "0(base)" although you can of course crop off any such yourself. |
| Example: |
?to_integer("12") -- 12
?to_integer("-12") -- -12
?to_integer("abc") -- 0 (the default def_value)
|
| Implementation: | See builtins\to_int.e (an autoinclude) for details of the actual implementation. |
| See Also: | to_number |