Parsing text...again

Authoring Inform 6
1

Dear all,

I have a switch that you can set to left, middle or right. Works fine like this:

before [;

SetTo:

switch(second){

‘left’:
etc.

Now I want to allow “switch switch to left|middle|right” as well without removing the normal switch function. So I extend the grammar:

Extend only ‘switch’ first * noun ‘to’ topic → Verb_MySwitch;

According to the parser output in “actions” mode it seems to me that no “second” argument is passed to my Verb_MySwitchSub routine:

switch switch to right
[ Action Verb_MySwitch with noun 245 (switch) ]

Question 1: What do I need to do to be able to parse for left|middle|right in my Verb_MySwitchSub routine?
Question 2: Since I do have the desired code in the switch object, I’d intuitively just use <> in the Verb_MySwitchSub routine, but how do I pass on the left|middle|right text?

Thanks!!!

2

If you look at Grammar.h, you’ll see that set is defined this way:

Verb 'set' 'adjust'
    * noun                                      -> Set
    * noun 'to' special                         -> SetTo;

So this works:

[ Verb_MySwitchSub;
	<<SetTo switch second>>;
];

Extend only 'switch' first * noun 'to' special -> Verb_MySwitch;
1 Like
3

I’m thinking that "flip switch " or “set switch to” is preferable to “switch switch”, but it sure is nice that inform allows to do so easily.

4

It works! Thanks Zarf!!!

5

Alternatively, you might be able to use:

Extend only 'switch' first
  * noun 'to' special -> SetTo;

I think this does the same as Zarf’s solution, but it doesn’t need the redundant Verb_MySwitch action.