11.3.142 number_codes/2 [ISO]

Synopsis

number_codes(+Number, -Codes)

number_codes(-Number, +Codes)

Codes is the codes comprising the printed representation of Number.

Arguments

Number

number

Codes

codes

Description

Initially, either Number must be instantiated to a number, or Codes must be instantiated to a proper codes.

If Codes is instantiated to a codes that corresponds to the correct syntax of a number, Number will be unified with that number.

Else, Number should be instantiated to a number, and Codes will be unified with the codes that make up its printed representation.

Exceptions

instantiation_error

Number and Codes are both uninstantiated

type_error

Number is not a number or Codes is not a list

domain_error

Codes is not a codes

representation_error

Codes is a list corresponding to a number that can't be represented

syntax_error

Codes does not correspond to a syntactically valid number

Examples

     | ?- number_codes(foo, L).
     
     ! Type error in argument 1 of number_codes/2
     ! expected a number, but found foo
     ! goal:  number_codes(foo,_104)

     | ?- number_codes(431, L).
     
     L = [52,51,49]

     | ?- number_codes(X, [102,111,111]).
     
     ! Syntax error in number_codes/2
     ! number syntax
     ! in line 0

     | ?- number_codes(X, [52,51,49]).
     
     X = 431

     | ?- number_codes(X, "15.0e+12").
     
     X = 1.5E+13

See Also

number_chars/2.