NAME
String::Numeric - Determine whether a string represents a numeric value
SYNOPSIS
$boolean = is_float($string);
$boolean = is_decimal($string);
$boolean = is_int($string);
$boolean = is_int8($string);
$boolean = is_int16($string);
$boolean = is_int32($string);
$boolean = is_int64($string);
$boolean = is_int128($string);
$boolean = is_uint($string);
$boolean = is_uint8($string);
$boolean = is_uint16($string);
$boolean = is_uint32($string);
$boolean = is_uint64($string);
$boolean = is_uint128($string);
DESCRIPTION
A numeric value contains an integer part that may be prefixed with an optional minus sign, which may be followed by a fractional part and/or an exponent part.
See "String::Numeric ABNF" for specification and "COMPARISON" for a comparison with "Scalar::Util::looks_like_number()".
FUNCTIONS
is_float
Determine whether $string is a floating-point number of arbitrary
precision.
Usage
$boolean = is_float($string);
$boolean = is_float('-1'); # true
$boolean = is_float('1'); # true
$boolean = is_float('1.0'); # true
$boolean = is_float('1.0e6'); # true
$boolean = is_float('1e6'); # true
$boolean = is_float(undef); # false
Arguments
$string
Returns
$boolean
Note
This function is also available as "is_numeric()"
is_decimal
Determine whether $string is a decimal number of arbitrary precision.
Usage
$boolean = is_decimal($string);
$boolean = is_decimal('-1'); # true
$boolean = is_decimal('1'); # true
$boolean = is_decimal('1.0'); # true
$boolean = is_decimal('1.0e6'); # false
$boolean = is_decimal('1e6'); # false
$boolean = is_decimal(undef); # false
Arguments
$string
Returns
$boolean
is_int
Determine whether $string is an integer of arbitrary precision.
Usage
$boolean = is_int($string);
$boolean = is_int('1'); # true
$boolean = is_int('-1'); # true
$boolean = is_int('1.0'); # false
$boolean = is_int(undef); # false
Arguments
$string
Returns
$boolean
Note
This function is also available as "is_integer()"
is_int8
Determine whether $string is a 8-bit signed integer which can have any
value in the range -128 to 127.
Usage
$boolean = is_int8($string);
$boolean = is_int8('-128'); # true
$boolean = is_int8('127'); # true
$boolean = is_int8(undef); # false
Arguments
$string
Returns
$boolean
is_int16
Determine whether $string is a 16-bit signed integer which can have any
value in the range -32,768 to 32,767.
Usage
$boolean = is_int16($string);
$boolean = is_int16('-32768'); # true
$boolean = is_int16('32767'); # true
$boolean = is_int16(undef); # false
Arguments
$string
Returns
$boolean
is_int32
Determine whether $string is a 32-bit signed integer which can have any
value in the range -2,147,483,648 to 2,147,483,647.
Usage
$boolean = is_int32($string);
$boolean = is_int32('-2147483648'); # true
$boolean = is_int32('2147483647'); # true
$boolean = is_int32(undef); # false
Arguments
$string
Returns
$boolean
is_int64
Determine whether $string is a 64-bit signed integer which can have any
value in the range -9,223,372,036,854,775,808 to
9,223,372,036,854,775,807.
Usage
$boolean = is_int64($string);
$boolean = is_int64('-9223372036854775808'); # true
$boolean = is_int64('9223372036854775807'); # true
$boolean = is_int64(undef); # false
Arguments
$string
Returns
$boolean
is_int128
Determine whether $string is a 128-bit signed integer which can have any
value in the range -170,141,183,460,469,231,731,687,303,715,884,105,728
to 170,141,183,460,469,231,731,687,303,715,884,105,727.
Usage
$boolean = is_int128($string);
$boolean = is_int128('-170141183460469231731687303715884105728'); # true
$boolean = is_int128('170141183460469231731687303715884105727'); # true
$boolean = is_int128(undef); # false
Arguments
$string
Returns
$boolean
is_uint
Determine whether $string is an unsigned integer of arbitrary precision.
Usage
$boolean = is_uint($string);
$boolean = is_uint('1'); # true
$boolean = is_uint('-1'); # false
$boolean = is_uint('1.0'); # false
$boolean = is_uint(undef); # false
Arguments
$string
Returns
$boolean
is_uint8
Determine whether $string is a 8-bit unsigned integer which can have any
value in the range 0 to 255.
Usage
$boolean = is_uint8($string);
$boolean = is_uint8('0'); # true
$boolean = is_uint8('255'); # true
$boolean = is_uint8(undef); # false
Arguments
$string
Returns
$boolean
is_uint16
Determine whether $string is a 16-bit unsigned integer which can have
any value in the range 0 to 65,535.
Usage
$boolean = is_uint16($string);
$boolean = is_uint16('0'); # true
$boolean = is_uint16('65535'); # true
$boolean = is_uint16(undef); # false
Arguments
$string
Returns
$boolean
is_uint32
Determine whether $string is a 32-bit unsigned integer which can have
any value in the range 0 to 4,294,967,295.
Usage
$boolean = is_uint32($string);
$boolean = is_uint32('0'); # true
$boolean = is_uint32('4294967295'); # true
$boolean = is_uint32(undef); # false
Arguments
$string
Returns
$boolean
is_uint64
Determine whether $string is a 64-bit unsigned integer which can have
any value in the range 0 to 18,446,744,073,709,551,615.
Usage
$boolean = is_uint64($string);
$boolean = is_uint64('0'); # true
$boolean = is_uint64('18446744073709551615'); # true
$boolean = is_uint64(undef); # false
Arguments
$string
Returns
$boolean
is_uint128
Determine whether $string is a 128-bit unsigned integer which can have
any value in the range 0 to
340,282,366,920,938,463,463,374,607,431,768,211,455.
Usage
$boolean = is_uint128($string);
$boolean = is_uint128('0'); # true
$boolean = is_uint128('340282366920938463463374607431768211455'); # true
$boolean = is_uint128(undef); # false
Arguments
$string
Returns
$boolean
LIMITATIONS
"String::Numeric" supports numbers in decimal notation using Western Arabic numerals and decimal fractions seperated with a dot. Other notations or numeral systems are not supported.
COMPARISON
Scalar::Util
None of the following is considered valid by "String::Numeric".
looks_like_number("1.") # true looks_like_number(".1") # true
looks_like_number("+1") # true
looks_like_number("01") # true
looks_like_number("1,1") # true assuming locale is in effect and locale radix point is ','
looks_like_number("\n1") # true looks_like_number("1\n") # true looks_like_number("\n1\n") # true
looks_like_number("Inf") # true looks_like_number("Infinity") # true looks_like_number("NaN") # true looks_like_number("0 but true") # true
GRAMMAR
String::Numeric ABNF
; String::Numeric ABNF Grammar
is-float = [ "-" ] FloatNumber
is-decimal = [ "-" ] DecimalNumber
is-integer = [ "-" ] DecimalInteger
is-uint = DecimalInteger
FloatNumber = DecimalNumber [ ExponentPart ]
DecimalNumber = DecimalInteger [ FractionalPart ]
DecimalInteger = "0" / ( NonZeroDigit DecimalDigit )
DecimalDigit = %x30-39; 0-9
NonZeroDigit = %x31-39; 1-9
FractionalPart = "." 1DecimalDigit
ExponentIndicator = "e" / "E"
ExponentPart = ExponentIndicator [ "+" / "-" ] 1*DecimalDigit
looks_like_number ABNF
; ABNF Grammar based on 5.10 Perl_grok_number()
looks-like-number = Number / ZeroButTrue
Number = *WS [ Sign ] ( FloatNumber / ( Infinity / NaN ) ) *WS;
FloatNumber = DecimalNumber [ ExponentPart ]
DecimalNumber = DecimalInteger [ "." DecimalDigit ] / "." 1DecimalDigit
DecimalInteger = 1DecimalDigit
WS = %x09 ; HT
/ %x0A ; LF
/ %x0C ; FF
/ %x0D ; CR
/ %x20 ; SP
DecimalDigit = %x30-39; 0-9
Sign = "+" / "-"
ExponentIndicator = "e" / "E"
ExponentPart = ExponentIndicator [ Sign ] 1DecimalDigit
Infinity = "Inf" / "Infinity"
NaN = "NaN"
ZeroButTrue = %x30.20.62.75.74.20.74.72.75.65 ; 0 but true
EXPORTS
None by default. Functions and constants can either be imported individually or in sets grouped by tag names. The tag names are:
":all" exports all functions.
":is_int" exports all "is_int" functions.
":is_uint" exports all "is_uint" functions.
DIAGNOSTICS
(F) Usage: %s(string)
Subroutine %s invoked with wrong number of arguments.
ENVIRONMENT
Set the environment variable "STRING_NUMERIC_PP" to a true value before loading this package to disable usage of XS implementation.
PREREQUISITES
Run-Time
perl 5.006 or greater.
Carp, core module.
Exporter, core module.
Build-Time
In addition to Run-Time:
Test::More 0.47 or greater, core module since 5.6.2. Test::Exception.
SEE ALSO
String::Numeric::XS
Data::Types
Regexp::Common::number
Scalar::Util
Scalar::Util::Numeric
AUTHOR
Christian Hansen "chansen@cpan.org"
COPYRIGHT AND LICENSE
Copyright 2009 Christian Hansen.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.