parser: resolve ambiguity where both prefix and primary actions are defined...
parser: resolve ambiguity where both prefix and primary actions are defined
If both actions are defined, a primary-expression action is accepted only if
the next token never starts new term. For example,
parsed as primary expression:
":" # next token 'end' has no action
"(:)" # next token ')' has no action
":+y" # next token '+' is infix operator
parsed as prefix operator:
":y" # next token 'y' is primary expression
":-y" # next token '-' is prefix operator
This is mostly the same resolution as the infix/suffix rules.
