The Palaiologos dialect has some features, that run counter to the assumptions of a line-oriented dialect like Burghard:
- A bare integer is a
pushwithout a mnemonic. - Opcodes with multiple arguments use
,to separate them (store).
Instructions are now no longer guaranteed to start with a mnemonic, so that should not receive special placement in the struct. Additionally, as seen with the unsplice transform, this placement separate from arguments makes manipulating spaces after the mnemonic more annoying.
Instead, the mnemonic and arguments should be unified into a separated list,
Separated<T, U>, like syn Punctuated<T, U>,
which is iterable with the spaces before and after.
Each dialect defines different types for the arguments accepted by opcodes, but they follow general patterns. Since only a few combinations of types and arities are used, an enum is appropriate. Any identical type combinations that generate different Whitespace instructions need different variants.
When parsing, a dialect often overloads the arguments accepted by an opcode; store the possible signatures as a bitset. Each parsed instruction is tagged with its signature.
The mnemonic is included in the signature, so that mnemonic-less push can be represented.
Add error tokens tokens like Tolerant PHP Parser:
Missing is for a token expected to be present, but is not. Skipped is for an
extra token that can't be dealt with.
For example, a missing argument multiple , separators could use Missing for
the hole or Skipped for the comma.