Optimisation: Avoid set copies when compiling files

[leamingrad]

This PR aims to speed up file compilation by avoid unnecessary copying of sets.

Previously, the Scope class had methods of the form:

def names_in_use(self):
	names = self.names
    if self.parent_scope is not None:
        # This create a new set
        result = result | self.parent_scope.names_in_use()

    return names

These sets were used by various other codegen functions to check for membership. With large fluent files, this results in a lot of unnecessary set creation, as there might be many names added to a given scope.

This PR replaces these methods with query equivalents of the form:

def is_name_in_use(self, name: str) -> bool:
    if name in self.names:
        return True

    if self.parent_scope is None:
        return False

    return self.parent_scope.is_name_in_use(name)

By doing this we speed up compiling by about 60%. For the 10K line benchmark added in #30, it reduces the time from ~10s to ~4s.

Benchmark before

❯ ./compiler.py -k 10k --benchmark-warmup=off
================================================================================================= test session starts ==================================================================================================
platform darwin -- Python 3.10.14, pytest-8.2.1, pluggy-1.5.0
benchmark: 4.0.0 (defaults: timer=time.perf_counter disable_gc=False min_rounds=5 min_time=0.000005 max_time=1.0 calibration_precision=10 warmup=False warmup_iterations=100000)
rootdir: /Volumes/Code/fluent-compiler
configfile: pyproject.toml
plugins: anyio-4.3.0, hypothesis-6.102.6, benchmark-4.0.0
collected 4 items / 3 deselected / 1 selected                                                                                                                                                                          

compiler.py .                                                                                                                                                                                                    [100%]


----------------------------------------------- benchmark: 1 tests -----------------------------------------------
Name (time in s)                Min      Max    Mean  StdDev  Median     IQR  Outliers     OPS  Rounds  Iterations
------------------------------------------------------------------------------------------------------------------
test_file_with_10k_items     9.7863  10.1248  9.9234  0.1377  9.8794  0.2118       1;0  0.1008       5           1
------------------------------------------------------------------------------------------------------------------

Legend:
  Outliers: 1 Standard Deviation from Mean; 1.5 IQR (InterQuartile Range) from 1st Quartile and 3rd Quartile.
  OPS: Operations Per Second, computed as 1 / Mean
====================================================================================== 1 passed, 3 deselected in 69.96s (0:01:09) ======================================================================================

Benchmark after

❯ ./compiler.py -k 10k --benchmark-warmup=off
================================================================================================= test session starts ==================================================================================================
platform darwin -- Python 3.10.14, pytest-8.2.1, pluggy-1.5.0
benchmark: 4.0.0 (defaults: timer=time.perf_counter disable_gc=False min_rounds=5 min_time=0.000005 max_time=1.0 calibration_precision=10 warmup=False warmup_iterations=100000)
rootdir: /Volumes/Code/fluent-compiler
configfile: pyproject.toml
plugins: anyio-4.3.0, hypothesis-6.102.6, benchmark-4.0.0
collected 4 items / 3 deselected / 1 selected                                                                                                                                                                          

compiler.py .                                                                                                                                                                                                    [100%]


----------------------------------------------- benchmark: 1 tests ----------------------------------------------
Name (time in s)                Min     Max    Mean  StdDev  Median     IQR  Outliers     OPS  Rounds  Iterations
-----------------------------------------------------------------------------------------------------------------
test_file_with_10k_items     3.9957  4.0290  4.0099  0.0127  4.0051  0.0164       2;0  0.2494       5           1
-----------------------------------------------------------------------------------------------------------------

Legend:
  Outliers: 1 Standard Deviation from Mean; 1.5 IQR (InterQuartile Range) from 1st Quartile and 3rd Quartile.
  OPS: Operations Per Second, computed as 1 / Mean
=========================================================================================== 1 passed, 3 deselected in 29.47s ==========================================================================================

[spookylukey]

This looks great, thanks!

On my Linux box I'm seeing even bigger speedups, from ~28s to ~6s on the same benchmark.