Name

every — Returns true if all items of given sequence matches given criterion.

Synopsis

boolean every ( varname string ,
test_set sequence ,
test_expn boolean );

Description

The function creates a temporary local variable, whose name is specified by varname argument. Then, for every item of test_set sequence it calculates the test_expn boolean expression having set the created variable to that "current" item. If the value of expression is false, the function immediately returns false without processing the rest of test_set sequence. If all items of the sequence are probed without getting false, true is returned. (So if the sequence is empty, the function returns true).

In any case, temporary variable is destroyed on return.

This function is used in the implementation of "EVERY" logical operator in XQUERY, so you will probably use that operator in XQUERY expressions, not the function. This function may be useful in XPATH expressions and in XSLT stylesheets. It is not a part of library of standard XQUERY 1.0 functions.

Parameters

varname

Name of temporary variable

test_set

Sequence of items; these items will be tested by test_expn

test_expn

Boolean expression which should be calculated for items of test_set .

Return Types

Boolean

Examples

Example24.585.

This expression returns true if all reports have positive incomes recorded.

every('income_value', /report/income, $income_value > 0)

See Also

some()