Space as APL modifier

[JohnS|Dyalog]

I'm sure this has been tried before but I can't recall seeing it, so presumably it's either a silly idea or it's too difficult to implement. I'd like to know which.

Background: when typing APL characters we need an additional modifier, the APL key, to input characters such as ⍳ and ⍴. On Windows platforms this key is Ctrl and on other platforms it might be Alt or something else.

How about using the space-bar as the APL key?

Space would become a dual-role key (https://en.wikipedia.org/wiki/Modifier_key#Dual-role_keys). Pressing and releasing the key would send a space character in the normal way; pressing additional keys while the space key is down would generate the equivalent APL characters. For example, to input ⍳⍴⍵ one would: press space; type irw; release space.

There is a precedent for dual-role keys in APL. Some vendors have used the Alt key on Windows platforms as an APL modifier in addition to its standard role of invoking menus: typing while holding down Alt sends APL chars; pressing and releasing Alt selects (the first menu in) the menu bar.

Pros:
* Less pressure to type "chords" with the fingers of one hand.
* Fingers tend to stay in their "home" positions on the keyboard while typing APL characters.
* It outsources some of the typing effort to that under-used resource: the thumbs.

Cons:
* We'd have to disable auto-repeat for the space-bar but (auto-repeating) Tab would still be available for sending multiple blanks.
* When typing "hello world" I may find I don't release the space bar fully before pressing the "w" of "world". If this is the case, I'd need to retrain my fingers accordingly.
* It may be non-trivial for us to implement but there is some evidence on the internet that it's possible.

NB: this is just a personal "muse" and is certainly not an official Dyalog proposal. I'm wondering whether it's a non-starter or whether it's worth trying an experiment.

[MBaas]

That sounds exciting! IF it would be supported in the IME, then I'm much in favour of that.
I'm struggling with kbd-handling since I started editing a lot of external code-files...and there are always conflicts with shortcuts of the various applications.
But this is so exotic, that would conflict with none of my tools and it would be possible to use the same kbd-layout EVERYWHERE! :-)