Adds a universal retrospective toggle macro to Plover.
============MACROS============
TOGGLE_KEY
=toggle_key:Key_A,Key_B,....
Toggles keys A, B, etc. in prior stroke. The keys are written with their implicit hyphen. This means that keys in the beginning of steno order are written with a "-" to the right, and those towards the end are written with a "-" to the left. See examples for clarification.
Examples:
=toggle_key:S-
This toggles the S-key at the start of steno order in the prior stroke. For instance, STAR becomes TAR, and RAU becomes SRAU.
=toggle_key:*
This mimics the effect of the {*} macro (also known as =toggle_asterisk). Note the absense of a hyphen.
=toggle_key:R-,-R
This toggles both R-keys in steno order. For instance, if the preceeding stroke was HRUF, this macro replaces that with HUFR.
STROKE_NEGATIVE
=stroke_negative
Toggles ALL keys in steno order, effectively creating a "negative" stroke. I don't know why this would be useful, but maybe someone will find it so.
============NOTES============
This plugin is system-agnostic, so it can be used with whatever system you are using with Plover. I use the Palantype system, for which =toggle_key:-^ is a useful macro. Note that -^ is a key not found in standard English stenotype.