[ Strings and Atoms | The ECLiPSe Built-In Predicates | Reference Manual | Alphabetic Index ]

string_code(+String, +Index, -Code)

Succeeds if Code is the value of the Index'th byte in String
String
String
Index
Integer between 1 and the length of String
Code
Variable or Integer

Description

This predicate extracts the Index'th byte from the given string String. Bytes in the string are numbered from 1 (analogous to array indices in subscript/3 and arg/3).

Modes and Determinism

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

   string_code("abc", 1, 97).		% succeeds
   string_code("abc", 3, C).		% gives C = 99

   string_code("abc", 2, 100).		% fails

   string_code("abc", _, C).		% Error 4
   string_code(_, 1, C).		% Error 4
   string_code("abc", 1.5, C).		% Error 5
   string_code(abc, 1, C).		% Error 5
   string_code("abc", 0, C).		% Error 6
   string_code("abc", 4, C).		% Error 6

See Also

string_list / 2, char_code / 2