What Are the Alternative Tokens for '&&' and '||' in C ?

Alternative Tokens in C : The Emergence of 'and' and 'or'

In the realm of C , the boolean operators 'and' and 'or' have long been staples. However, some may be surprised to learn that they possess alternative tokens that mirror their primary representations. This intriguing aspect of C syntax has been present since the conception of the language itself.

The introduction of these alternative tokens can be traced back to the earliest days of the C standardization process, as detailed in the C 98 standard. Section 2.5/ Alternative tokens [lex.digraph] stipulates that:

"Alternative token representations are provided for some operators and punctuators. Each alternative token behaves the same as its primary token in all respects, except for its spelling."

Table 2 of the standard outlines the set of alternative tokens, including 'and' and 'or':

Alternative Token	Primary Token
'and'	'&&'
'or'	'		'

Despite their inclusion in the standard, these alternative tokens have remained largely unknown to many programmers. One possible reason for this obscurity is that their primary use case was in environments where certain characters, such as square brackets, were unavailable. For instance, on IBM mainframes with EBCDIC character sets, alternative tokens provided a workaround for the absence of square brackets.

In conclusion, the alternative tokens 'and' and 'or' have been part of the C language since its inception, enabling operators to be expressed using alternative spellings. Their presence in the standard, alongside their practical applications, makes them a fascinating aspect of C syntax.

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