filter: ${filter{<' a'b'c}{!eq{$item}{b}}}
filter: ${filter{<' ''a'b' ''c}{!eq{$item}{b}}}
filter: "${filter{}{!eq{$item}{b}}}"
+# check operation when the condition modifies the 'value' variable
+${filter {E} {inlisti{$item}{ e }}}
map: "${map{}{$item}}"
map: ${map{a:b:c}{$item}}