collapsed slot classes into one

different slot operation have different right sides
mom assignment tests work again
157 others don’t

lib/mom/README.md

@@ -38,43 +38,21 @@ So to put a layer in the middle of those two, MOM will be:
 
 ### Linked list
 
-But, see below, in two steps
+But, very much like Risc, just higher level so it's easier to understand
 
 ### Use object memory
 
 object to object transfer
 
-no registers
+no registers (one could see the current message as the only register)
 
 ### Instruction based
 
-So a machine rather than a language. No control structures, but compare and jump instructions.
+So mom is a machine layer, rather than a language.
+No control structures, but compare and jump instructions.
 
 No send or call, just objects and jump.
 
 Again in two steps, see below
 
 Machine capabilities (instructions) for basic operations. Use of macros for higher level.
-
-## Two step approach
-
-To make the transition even easier, it is done in two steps.
-
-## 1. Everything but control structures
-
-wSo we go from language to machine as the first step, in terms of memory instructions.
-Memory gets moved around between the main machine objects (frames and messages).
-But control structures stay "intact", so we stay at tree structure
-
-## 2. Flattening control structures
-
-By flattening control structures and introducing jumps instead, we go from tree to linked
-list of instructions.
-
-After this, it is quite trivial to translate to risc, as it mostly expands instructions.
-
-## The future
-
-I hope that in the future this simple 2 stage pipeline will expand into more steps.
-This is the ideal layer to do code analysis and meaningful optimisations, as one can still
-understand what is going on in higher terms.