Typeswitch expressions
JSONiq follows the W3C standard for ordered and unordered expressions. The following explanations, provided as an informal summary for convenience, are non-normative.
Figure 68. TypeswitchExpr
Figure 69. CaseClause
A typeswitch expressions tests if the value resulting from the first operand matches a given list of types. The expression corresponding to the first matching case is finally evaluated. If there is no match, the expression in the default clause is evaluated.
Example 167. Typeswitch expression
typeswitch("foo")
case integer return "integer"
case string return "string"
case object return "object"
default return "other"
Result (run with Zorba): string
In each clause, it is possible to bind the value of the first operand to a variable.
Example 168. Typeswitch expression
typeswitch("foo")
case $i as integer return $i + 1
case $s as string return $s || "foo"
case $o as object return [ $o ]
default $d return $d
Result (run with Zorba): foofoo
The vertical bar can be used to allow several types in the same case clause.
Example 169. Typeswitch expression
typeswitch("foo")
case $a as integer | string return { "integer or string" : $a }
case $o as object return [ $o ]
default $d return $d
Result (run with Zorba): { "integer or string" : "foo" }