Compiler/lexical analyzer: Difference between revisions
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Updated definition of whitespace.
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;White space
* Zero or more whitespace characters or comments are allowed between any two tokens, with the exceptions noted below.
* "longest token matching" is used to resolve conflicts (e.g., in order to match '''<=''' as a single token rather than the two tokens '''<''' and '''=''').
* Whitespace is only required in the following situations:
** To distinguish between keywords:
*** ifprint - is recognized as an identifier, instead of the keywords '''if''' and '''print'''.
** To distinguish between keywords and integers:
*** 42fred - is an invalid number or invalid identifier.
* Whitespace is not allowed between:
** Multi-character operators: These cannot be recognized unless they occur without embedded whitespace: '''&&''' '''<='''.
The following programs are equivalent:
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}
</lang>
Output from test case 3:
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</pre>
</b>
=={{header|Euphoria}}==
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</pre>
</b>
=={{header|Flex}}==
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