"eq" vs. "="

Question

What are the use cases for "eq" vs. "=" ?
What would be the difference between:
$person/t:PersonName/t:PersonSurName eq "CCH"
vs.
string ( $person/j:PersonName/j:PersonSurName ) eq "CCH"
vs.
$person/j:PersonName/j:PersonSurName = "CCH"
The first case reports "Type incompatible error"

Answer 1

$person/j:PersonName/j:PersonSurName is not a string - it is an element of type
string.
From http://www.awprofessional.com/articles/article.asp?p=100667&seqNum=6
"XQuery provides two sets of comparison operators. The general comparison operators,
=, !=, >, >=, <, and <=, which are inherited from XPath Version 1, have an implied
existential quantifier on both operands. For example, the expression A = B, if
A and B are sequences of multiple values, returns true if some item in sequence
A is equal to some item in sequence B. If either of their operands is an empty
sequence, the general comparison operators return false. "
"XQuery also provides a set of value comparison operators, eq, ne, gt, ge, lt,
and le, which require both of their operands to consist of exactly one atomic
value. "
"Benjamin Shrom" <[email protected]> wrote:
>
What are the use cases for "eq" vs. "=" ?
What would be the difference between:
$person/t:PersonName/t:PersonSurName eq "CCH"
vs.
string ( $person/j:PersonName/j:PersonSurName ) eq "CCH"
vs.
$person/j:PersonName/j:PersonSurName = "CCH"
The first case reports "Type incompatible error"