# Concat strings per-group

### Description
Concatenates all the strings that belong to the same "group",
which is identified by the `OBJ` in the first column.

Warning: the order in which the strings are concatenated is not predictable.

### Input
- `SOURCE [OBJ,STRING]`: a 2-column input with an object-string pair.

### Output 
- `RESULT [OBJ,STRING]`: the pairs from `SOURCE`, where strings with the same `OBJ` column have been concatenated
- `STRINGS [STRING]`: the concatenated strings, without the object they were paired to

### Parameters
- `Separator`: string to use as a separator between the concatenated strings (Default is a space)

Output scores can be [aggregated](docs://score_aggregation) and/or [normalised](docs://score_normalisation).