18.6.5. A Simple Rule Pattern Example
To better see how the macro substitution patterns operate, consider the following rule lefthand side:
$* < $+ >
This rule matches "Zero or more tokens, followed by the < character, followed by one or more tokens, followed by the > character."
If this rule were applied to brewer@vbrew.com or Head Brewer < > , the rule would not match. The first string would not match because it does not include a < character, and the second would fail because $+ matches one or more tokens and there are no tokens between the <> characters. In any case in which a rule does not match, the righthand side of the rule is not used.
If the rule were applied to Head Brewer < brewer@vbrew.com > , the rule would match, and on the righthand side $1 would be substituted with Head Brewer and $2 would be substituted with brewer@vbrew.com .
If the rule were applied to < brewer@vbrew.com > the rule would match because $* matches zero or more tokens, and on the righthand side $1 would be substituted with the empty string.
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