Several built-in, infix operators allow testing for equality and inequality. For numbers, <, >, <=, >=, ==, and !=Anchor
eq, neq, and like are used.Like takes a regular expression as its second argument and returns true if it matches the string given as its first argument. Arguments to these operators can be any valid expression.
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spicy = cheese like re/(nacho|pepperjack)/; |
The following are all valid predicate expressions:
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c == 5 |
...
page:var("city") eq "Blackfoot" |
...
"Lindon" neq location:city() |
...
weather:curr_temp() < 90 |
...
location:city() + ", WA" eq city |
...
5 * (weather:curr_temp() - 32) / 9 < 0 |
As can be seen from the preceding examples, a number of built-in libraries provide predicates that can be used inside predicate expressions. The documentation for those libraries gives details about their operation.
Compound predicate expressions are created using the operators &&, ||, and not to express conjunction, disjunction, and negation, respectively. Parentheses are used to group expressions for precedence.