xml - Create a list using a for in XQuery 1.0 -

i create list of element using in example:

for $ingr in distinct-values(//ingredient/name) let $res := (   $res2 in //restaurant   return if( $ingr2 in $res2/dish/ingredient/name satisfies $ingr2 eq $ingr )     then( $res2 )     else()   ) return $ingr, $res 

what want obtain is: for each ingredient return list of restaurants use it. don't understand problem?

here can see example: http://www.xpathtester.com/xquery/0c8f9699df404020afd07ff9f9517a46

it keep saying: error - variable $res has not been declared

your expression read (for ... let ... return $ingr), ($res). means $res @ end considered different expression separate previous flwor expression, hence undeclared variable error.

you can use parentheses alter unwanted grouping :

for $ingr in distinct-values(//ingredient/name) let $res := (   $res2 in //restaurant   return if( $ingr2 in $res2/dish/ingredient/name satisfies $ingr2 eq $ingr )     then( $res2 )     else()   ) return ($ingr, $res) 

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