Open rsaihe opened 2 years ago
This is (partially) addressed in #80.
For zigErrorSet
:
I think there are two hurdles to getting this syntax rule to work...
1) You can't tell by looking at just !x
whether it refers to an error set type or a logical-not.
2) Vim syntax rules shouldn't "feel around" for context. Processing should move from one rule to the next.
I've worked with rules like this before, and it's quite straight-forward to get things working correctly. For a syntax as sparse as Zig's, it may be even easier.
Here's a screenshot of my first update to the rules (based on the changes in #80):
The syntax rules require knowing the sequence of tokens to test. In this case, fn
may be followed by a contained
function name, followed by a contained
parameter list, followed by a type.
Like so:
" XXX Other zigType rules listed elsewhere.
" TODO Handle explicit error set type before the !.
syn match zigType "[!]\?[A-Za-z_][A-Za-z0-9_]*" contained
" FUNCTIONS {{{2
syn keyword zigKeyword fn skipwhite nextgroup=zigFunctionName
syn match zigFunctionName "[A-Za-z_][A-Za-z0-9_]*" contained skipwhite nextgroup=zigFunctionParams
syn region zigFunctionParams start="(" end=")" contained contains=TOP skipwhite nextgroup=zigType
The secondary, contextual rules are contained
, meaning they are only considered/tested when explicitly referenced by another rule. (In this case, that means zigFunctionParams
is only tested after zigFunctionName
is matched, etc.) No need for feeling around, and much less risk of ambiguous rules relying on syntax declaration order rather than actual meaning of the text.
nextgroup
provides a hint about the next rule to match. If it doesn't match the following name, life goes on. Here, I remove the !u8
from main
. Vim couldn't match the zigType
rule there, so it just carries on testing the other rules.
Bonus for this approach: free highlighting of smaller syntax elements, like function names in function declarations. :hi link zigFunctionName String
produces the following:
If you're interested in doing something like this and want some help writing/testing/debugging, let me know. 😊
There should be a special highlight group for the error set operator (!) and the optional operator (?). I propose the names
zigErrorSet
andzigOptional
for these highlight groups.Ideally it would be possible to have
zigErrorSet
not match the logical NOT operator (!), but I am not sure how such a thing might be implemented.zigErrorSet
andzigOptional
should be linked to the (currently unused)zigSpecial
highlight group.Additionally, I feel it would also make sense to create a new highlight group
zigDeref
for the pointer dereference operator, which could perhaps also be linked tozigSpecial
.? and ! in particular are quite important to pay attention to, so I feel it makes sense to allow them to be specially highlighted to make them more obvious when reading code.