Strings
String concatenation
String concatenation is made using the infix operator ||.
Examples:
'ab' || 'cd' || 'ef';
'ab' || 12 || 'de';
'ab' || 1 || 2
Concatenation of strings and other objects is implemented by the
generic system function concat(Object x,Object y)->Object.
String matching
A string str is matched against a regular expression pattern pat using
the infix operator str like pat. In a pattern % (or *) matches
a sequence of characters, while _ matches a single character. The
[chars] pattern matches any character in chars.
Examples:
'abc' like '__c'
'abc' like '%c'
'abc' like 'a[bd][dc]'
'abc' like 'a[bd][de]'
The like operator is implemented by the system function
like(Charstring str, Charstring pat)->Boolean.