Compare sequences.
A general comparison differs from a value comparison in that operands may be
sequences of any length with implicit existential quantification. Given two
sequences A
and B
the result is determined as
follows:
A = B
is true
if and only if the value
comparison a eq b
is true for some item a
in
A
and some b
in B
. Otherwise it is
false
.
A != B
is true
if and only if the value
comparison a ne b
is true for some item a
in
A
and some b
in B
.
A < B
is true
if and only if the value
comparison a lt b
is true for some item a
in
A
and some b
in B
.
A <= B
is true
if and only if the value
comparison a lt b
is true for some item a
in
A
and some b
in B
.
A > B
is true
if and only if the value
comparison a gt b
is true for some item a
in
A
and some b
in B
.
A >= B
is true
if and only if the value
comparison a ge b
is true for some item a
in
A
and some b
in B
.
For all books check if there is an author with surname "Stevens":
for $b in input()/bib/book return $b/author/last = "Stevens"
Given the sample data this comparison is true
for two
instances of book
, but false
for the
other ones.
The following construct(s) refer to this construct:
This construct is also related to the following construct(s):
ValueComp
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