Retrieves or checks the lexical class of a given character.
Class is unified with the current lexical character class of Char.
Char must be an integer character code, which would typically be
written in character-quote syntax, eg 0'a instead of 98.
The following table lists the existing character classes and the default set of characters in that class:
Class Default member characters
---------------------------------------------------------
upper_case all upper case letters
underline _
lower_case all lower case letters
digit digits
blank_space space, tab and nonprintable characters
end_of_line newline (NL)
atom_quote '
string_quote "
list_quote `
chars_quote
radix
ascii
solo ! ;
special ( [ { ) ] } , |
line_comment %
escape \
first_comment /
second_comment *
symbol # + - . : < = > ? @ ^ ~ & $
terminator
The table corresponds to the default eclipse_language settings. Using other language dialects typically changes some of the assignments on a module-local basis (e.g. for the iso dialect, the meaning of single and double quotes is reversed).
Note: the default class of the back-quote character ` was changed from symbol to list_quote in ECLiPSe 7.0.
Success:
[eclipse]: get_chtab(0'a,X).
X = lower_case
yes.
[eclipse]: get_chtab(60,X).
X = symbol
yes.
[eclipse]:
Fail:
get_chtab(98,symbol).
get_chtab(98,blah).
Error
get_chtab(X,lower_case). (Error 4).
get_chtab("a",X). (Error 5).
get_chtab(-1,X). (Error 6).