Will I get a faster parser using spirit X3 when I use the expect operator

Question

In spirit X3 I can build a parser like this:

const auto p = ("Number:" >> x3::_int)
             | ("String:" >> +x3::alpha);

If I know after the string Number comes a int and after String a string all the time I can use the > to say after Number only comes a number and so on.

const auto p = ("Number:" > x3::_int)
             | ("String:" > +x3::alpha);

For me the difference is if the parser fails to parse the input an exception is throw.

Now my question is, should I use the > operater over the >> operater whenever possible? Is the parser which will be generated using > faster then the one only using the >> operator?

Answer 1

You should always just profile things.

Regardless:

Will I get a faster parser using spirit X3 when I use the expect operator

Only to the extent that it prevents backtracking alternatives, but if you needed that it's not doing the same anyways.