Xpressionist expects an operator that defines the operation between values. Arguments for functions are divided by commas. This error also arises if you have forgotten to terminate the expression. Xpressionist assumes the statement to be continued in the next line and often expects an operator here.

This does not work:

a = m n;

b = vec( 1 2 3 );

You must define an operation or put commas between arguments:

a = m + n;

b = vec( 1, 2, 3 );