@Override
    public String toString(ToStringContext<NAMETYPE> context) {
        return "concat(" + argumentA.toString(context) + ", " + argumentB.toString(context) +
               ", " + context.resolveBinding(dimension) + ")";
    }
Concatenation of two tensors along an (indexed) dimension

@author bratseth
vespajlib/src/main/java/com/yahoo/tensor/functions/Concat.java