message: Begin describing operational semantics
diff: # Operational syntax
  TODO
  +
  +## Evaluation
  +
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` <var>term</var>`)` | <var>value</var> |
  +| - | - |
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` `univ(`<var>level</var>`))` | `univ(`<var>level</var> + <var>offset</var>`)` |
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` `local(`<var>name</var>`))` | `local(`<var>name</var>`)` |
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` `global(`<var>name</var>`))` | `global(`<var>name</var>`)` |
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` `constant(`<var>constant</var>`))` | `constant(`constant`)` |
  +| `eval(`<var>globals</var>`,` <var>offset</var>`,` `ann(`<var>term</var>`,` <var>type</var>`))` | `eval(`<var>globals</var>`,` <var>offset</var>`,` <var>term</var>`)` |
  +| &hellip; | &hellip; |
  +| `eval(`<var>globals</var>`,` <var>offset</var><sub>0</sub>`,` `lift(`<var>term</var>`,` <var>offset</var><sub>1</sub>`))` | `eval(`<var>globals</var>`,` <var>offset</var><sub>0</sub> + <var>offset</var><sub>1</sub>`,` <var>term</var>`)` |
  +
  +## Read-back
  +
  +| `read-back(`<var>value</var>`,`<var>value</var>`)` | <var>term</var> |
  +| - | - |
  +| &hellip; | &hellip; |
  