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get_string_code(+Index, +String, -Code)
Succeeds if Code is the value of the Index'th character code in String
- Index
- Integer between 1 and the length of String
- String
- String
- Code
- Variable or Integer
Description
    This predicate extracts the Index'th character code from the given
    string String.  Character codes in the string are numbered from 1
    (analogous to array indices in subscript/3 and arg/3).
    
    Note that (like all predicates that return a number as their last
    argument), this predicate can be used as a function inside arithmetic
    expressions.
Modes and Determinism
- get_string_code(+, +, -) is det
Exceptions
- (5) type error 
- Index is not an integer
- (5) type error 
- String is not a string
- (5) type error 
- Code is instantiated but not to an integer
- (6) out of range 
- Index is an integer less than 1 or greater than String's length
- (4) instantiation fault 
- Either Index or String are uninstantated
Examples
   get_string_code(1, "abc", 97).     % succeeds
   get_string_code(3, "abc", C).      % gives C = 99
   get_string_code(2, "abc", 100).    % fails
   get_string_code(_, "abc", C).      % Error 4
   get_string_code(1, _, C).          % Error 4
   get_string_code(1.5, "abc", C).    % Error 5
   get_string_code(1, abc, C).        % Error 5
   get_string_code(0, "abc", C).      % Error 6
   get_string_code(4, "abc", C).      % Error 6
See Also
string_code / 3, string_codes / 2, string_list / 2, char_code / 2