path: root/doc/info/chap/language-facilities.texinfo

@node Language facilities
@chapter Language facilities



@menu
* Alternative tokens::                        Alternative spellings of common operators.
@end menu



@node Alternative tokens
@section Alternative tokens

@hfindex iso646.h
@cpindex Alternative tokens
@cpindex Tokens, alternative
The C90 standard was amended in 1995 to include
alternative spellings of common operators, referred
to as C alternative tokens.

@table @code
@item and
@fnindex and
@code{&&}

@item and_eq
@fnindex and_eq
@code{&=}

@item bitand
@fnindex bitand
@code{&}

@item bitor
@fnindex bitor
@code{|}

@item compl
@fnindex compl
@code{~}

@item not
@fnindex not
@code{!}

@item not_eq
@fnindex not_eq
@code{!=}

@item or
@fnindex or
@code{||}

@item or_eq
@fnindex or_eq
@code{|=}

@item xor
@fnindex xor
@code{^}

@item xor_eq
@fnindex xor_eq
@code{^=}
@end table

These alternative spellings are implemented as a
group of macro constants, and are made available
by including the header file @file{<iso646.h>}.
They were added because a concern that the standard
names are difficult to type on some keyboard-layouts.

Use of these alternative tokens are discouraged,
they lessen the readability of your code. If it is
difficult to type some characters without yout
keyboard-layout, it is better to change keyboard-layout.