It's possible to repeat parameters in method definitions like so:
```ruby
def foo(_a, _a)
end
```
The compiler needs to know to adjust the local table size to account for
these duplicate names. We'll use the repeated parameter flag to account
for the extra stack space required
b443cb1f60
Co-Authored-By: Kevin Newton <kddnewton@gmail.com>
Co-Authored-By: Jemma Issroff <jemmaissroff@gmail.com>
Previously numbered parameters were a field on blocks and lambdas
that indicated the maximum number of numbered parameters in either
the block or lambda, respectively. However they also had a
parameters field that would always be nil in these cases.
This changes it so that we introduce a NumberedParametersNode that
goes in place of parameters, which has a single uint8_t maximum
field on it. That field contains the maximum numbered parameter in
either the block or lambda.
As a part of the PR, I'm introducing a new UInt8Field type that
can be used on nodes, which is just to make it a little more
explicit what the maximum values can be (the maximum is actually 9,
since it only goes up to _9). Plus we can do a couple of nice
things in serialization like just read a single byte.
2d87303903
Fundamentally, `foo { |bar,| }` is different from `foo { |bar, *| }`
because of arity checks. This PR introduces a new node to handle
that, `ImplicitRestNode`, which goes in the `rest` slot of parameter
nodes instead of `RestParameterNode` instances.
This is also used in a couple of other places, namely:
* pattern matching: `foo in [bar,]`
* multi target: `for foo, in bar do end`
* multi write: `foo, = bar`
Now the only splat nodes with a `NULL` value are when you're
forwarding, as in: `def foo(*) = bar(*)`.
dba2a3b652
Prior to this commit, KeywordParameterNode included both optional
and required keywords. With this commit, it is split in two, with
`OptionalKeywordParameterNode`s no longer having a value field.
89084d9af4
