is_graph(+character)

This predicate checks if the character argument is a printable character but not a whitespace. It succeeds if this is so, else it fails.

see also: &/2 delete/3 insert/3 is/2  is_alpha/1 is_alphanum/1 is_ascii/1 is_cntrl/1 is_digit/1 is_lower/1 is_upper/1 is_space/1 substring/3 string_list/2 working with strings

Examples
is_graph(1). succeeds because 1 is a graphical character
is_graph('\t'). fails because the tab character is not a graphical character

 

Exceptions
The  parameter is an empty variable an instantiation_error exception is thrown
The parameter is a list a type_error(character, Arg) exception is thrown and Arg is replaced by the value of the parameter
The parameter is an integer that exceeds the specified range of integers an evaluation_error(int_overflow) exception is thrown
The parameter is not a correct character a type_error(character, Arg) exception is thrown and Arg is replaced by the value of the parameter

 

 

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