Allow adding Debug button to #lang languages

[mikesperber]

Fixes racket/htdp#177

[soegaard]

@rfindler This PR seems to be forgotten?

[rfindler]

Thank you for the reminder @soegaard ! I did somehow miss this one.

@mikesperber I think that maybe changing something around here based on these docs is a better way to go. Does that not work?

[mikesperber]

@mikesperber I think that maybe changing something around here based on these docs is a better way to go. Does that not work?

Yes: But that has this as a prerequisite.

[rfindler]

@mikesperber I think that maybe changing something around here based on these docs is a better way to go. Does that not work?

Yes: But that has this as a prerequisite.

When I change the quoted code to have these two lines:

    [(drscheme:opt-out-toolbar-buttons)
     '(macro-stepper)]

(instead of returning #f from that case), then I see a debug button and clicking on it seems to turn on the debugger.

Can you please elaborate on what you tried and how it goes wrong that led you to want to make modifications to drracket itself here?

[mikesperber]

@rfindler Ah, you mean the bottom line of that snippet, not the top lines. (The docs you quote are almost impossible to find if you don't know about them beforehand.)

I was following the example of the syntax-check and stepper buttons - the top lines of the snippet.

Shouldn't those be done the same way?

[rfindler]

@rfindler Ah, you mean the bottom line of that snippet, not the top lines.

You may need to change all the lines, I guess.

I was following the example of the syntax-check and stepper buttons - the top lines of the snippet.

Shouldn't those be done the same way?

Adding things to the code that's shared between various parts of drracket and the namespace in the interactions window should be done as infrequently as possible. When there is more shared, then it can get difficult to ensure that, for example, hitting the Run button really does reset the program that's being run.

[rfindler]

I'm still seeing two "Check Syntax" buttons in the teaching languages ASL with the current commit.