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+# echse
+
+The cutest assembly-like language!
+
+This is for learning or teaching purposes only - and is probably not useful for anything else.
+
+## From code to running
+
+1. Code with macros (.es)
+2. Preprocessor applies macros and resolves jump labels (.ei)
+3. Transform into binary representation (.eo)
+4. Run the binary
+
+Currently, you have to write and execute a .ei file.
+
+## Ideas and ToDos
+
+- a cute manual for the provided functionality
+- preprocessor that supports jumping to labels and unrolled loops
+- separate machine configuration and program in files
+- register custom instructions before parsing
+- optional stack with pus, pop, ret
+- small games built upon this:
+    - battle multiple programs against each other
+    - rustlings-like exercises to learn the instructions
+    - put multiple echsen into an environment, interact with environment
+
+## Limitations
+
+List of constraints that I want to keep:
+
+- general-purpose registers
+  - are always interpreted as native signed integers
+  - are numbered r0...rn, without gaps
+- all base instruction
+  - have names with 3 letters
+  - all test instructions start with i (after prefixes) and always set r0
+  - all conditional jumps act based upon r0
+  - when interpreting numbers as booleans: 0 is false, everything else is true. The name of instructions should reflect that. 
+- all extension instructions
+  - have names longer than 3 letters
+  - have a extension prefix
+- the executed instructions do not know anything about the preprocessor and all formatting and jump marks are lost
+- there should be no hard-coded calling convention
+
+## License
+
+The code in this repository is licensed under GPL v2 or later, unless stated otherwise in the file.