Nested parse expressions
Parse expressions can be nested and are evaluated in parenthetical order. There is no practical limit to nesting parse expressions. Any specifications can substitute any parse-spec value with another nested parse-spec value.
The following examples show target strings, parse expressions, and return values:
Target string | Parse expression | Return value |
|---|---|---|
Test1|README.txt | $basename ($delim(pipe, 2)) | README Explanation: The function returns the base name of the second field that is delimited by a pipe. |
user account: AA|BB|CC – user account: DD|EE|FF | $skip (user account, 2, $delim (pipe, 2)) | EE Explanation: The function returns the second pipe-delimited word following the second match for user account. |
user account: AA|BB|CC – user account: DD|EE|FF | $delim (pipe, $skip (user account, 2, 2)) | EE Explanation: This alternate expression returns the same value as in the preceding example. |
test addr: x@y.z | $match (test, $email (addr: *))
| x@y.z Explanation: The expression parses the email address only if the keyword test appears in the string. |
test addr: x@y.z | $exclude (test, $email (addr: *)) | No match Explanation: The message contains the word test, which is excluded in the expression. |
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