XQuery/Sequences Module

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Motivation[edit | edit source]

You want to perform a function on a sequence. You can one of the following functions: map, fold or filter.

Method[edit | edit source]

Here is the structure of these three functions.

  sequences:map($func as function, $seqA as item()*, $seqB as item()*) as item()*
  sequences:fold($func as function, $seq as item()*, $start as item())
  sequences:filter($func as function, $seq as item()*) as item()*

Each of them takes an XQuery function as the first argument.

Map[edit | edit source]

The map function applies the function item $f to every item from the sequence $seq in turn, returning the concatenation of the resulting sequences in order.

W3C Page on Map

Fold[edit | edit source]

Filter[edit | edit source]