Copied from mailing list by Liam -
https://lists.w3.org/Archives/Member/w3c-xsl-query/2014Apr/0036.html


This is an attempt to flesh out an idea from Mohamed (see https://lists.w3.org/Archives/Member/w3c-xsl-query/2014Feb/0065.html).

1. map1  + map2 

If a and b are both maps, then a  + b is defined as map:new( a, b).  The following expressions are equivalent:

$m2 := map:new( $m1, { "foo" : "bar" }) 
$m2 := $m1 + { "foo" : "bar" }


2. map - atomic

If a is a map and b is an atomic value, then a - b is defined as map:remove(a, b). The following expressions are equivalent:

$m2 := map:remove( $m1, "foo") 
$m2 := $m1 - "foo"

Jonathan