Concatenation
string-functions concatenation (+)
syntax
- add(string_dataitem_a,string_dataitem_b)
- string_dataitem_a + string_dataitem_b
definition
add(string_dataitem_a,string_dataitem_b) or string_dataitem_a + string_dataitem_b + … results in the element-by-element concatenation of corresponding string values of arguments: string_dataitem_a and string_dataitem_b.
description
The + operator is also in use for numeric additions. String concatenations differ from normal additions, they are not commutative (a + b is not equal to b + a).
applies to
- data items with string value-type
conditions
The domain units of all arguments must match or be void (string literals and parameters can be concatenated with any string data item.
example
attribute<string> AandB (ADomain) := A + B;
| A | B | AandB |
|---|---|---|
| ‘Test’ | ‘Test2’ | ‘TestTest2’ |
| ‘88hallo99’ | null | null |
| ’+)’ | ’-‘ | ’+)-’ |
| ‘twee woorden’ | ‘drie woorden test’ | ‘twee woordendrie woorden test’ |
| ’ test met spatie’ | ’ _woord’ | ’ test met spatie _woord’ |
ADomain, nr of rows = 5