(Go) Lox (Crafting interpreters)

This is an implementation of The Lox Programming Language implemented in Go.

Current status:

• Feature Complete as passing original test suite, see below.
• Benchmarks comparable to jlox (java version), see below.

eXtra Features

• REPL expression output; readline support.
• block comments.
• continue, break statements.
• closures and anynymous functions.
• native functions: Array, pprint(...) varargs function.
• profiles: -profile=non-strict (test compliance) and -profile=strict [default] to report unused variables.
• Static class methods, and class properites (metaclass).

How-To

Use provided make commands

$ make help
Usage: make <target>
 Default
        help                  Display this help
 Build/Run
        all                   ALL, builds the world
        clean                 Clean-up build artifacts
        gen                   Runs all codegen
        test                  Runs all tests
        lint                  Runs all linters
        run                   Runs golox. Use ARGS="" make run to pass arguments

Test Suite

See test/ folder with a copy of original testsuite from https://github.com/munificent/craftinginterpreters/tree/master/test.

runner_test.go:69: Suite golox: Tests=254, Passed=238, Failed=0, Skipped=16, Expectations: 557

Excluded tests (conflicts with eXtra features):

• test/field/get_on_class.lox.
• test/field/set_on_class.lox.

Benchmarks

Command used:

go test -v -run=XXX -bench=. -benchtime=30s -timeout=30m ./test/.

The benchmark work as follows:

• executes bin/golox and jlox from original project.
• benchmarks reports execution time and becnhmark elapsed time as printed by bechnmark script.

Please find numbers below:

# Formatted output
BenchmarkAll
GO/test/benchmark/equality.lox-8                6 5009233757 ns/op       0.3980 elapsed/op
JAVA/test/benchmark/equality.lox-8              8 4237118536 ns/op       0.7470 elapsed/op
GO/test/benchmark/binary_trees.lox-8            4 9035542448 ns/op       8.914 elapsed/op
JAVA/test/benchmark/binary_trees.lox-8          6 5911415000 ns/op       5.846 elapsed/op
GO/test/benchmark/properties.lox-8              7 4927545500 ns/op       5.334 elapsed/op
JAVA/test/benchmark/properties.lox-8            7 4493170381 ns/op       4.385 elapsed/op
GO/test/benchmark/invocation.lox-8             10 3288547812 ns/op       3.097 elapsed/op
JAVA/test/benchmark/invocation.lox-8           37  867685619 ns/op       0.7800 elapsed/op
GO/test/benchmark/fib.lox-8                     4 8474984490 ns/op       8.397 elapsed/op
JAVA/test/benchmark/fib.lox-8                   4 7828719094 ns/op       7.744 elapsed/op
GO/test/benchmark/trees.lox-8                   2 23599520333 ns/op      21.59 elapsed/op
JAVA/test/benchmark/trees.lox-8                 2 21246922084 ns/op      20.97 elapsed/op
GO/test/benchmark/string_equality.lox-8         4 8742849177 ns/op       4.145 elapsed/op
JAVA/test/benchmark/string_equality.lox-8       7 4765044637 ns/op       2.694 elapsed/op
GO/test/benchmark/instantiation.lox-8          12 3103455396 ns/op       3.037 elapsed/op
JAVA/test/benchmark/instantiation.lox-8        37  879199985 ns/op       0.8210 elapsed/op
GO/test/benchmark/zoo_batch.lox-8               3 10016985805 ns/op      10.02 elapsed/op
JAVA/test/benchmark/zoo_batch.lox-8             3 10068449986 ns/op      10.00 elapsed/op
GO/test/benchmark/method_call.lox-8            22 1432509085 ns/op       1.429 elapsed/op
JAVA/test/benchmark/method_call.lox-8          22 1625271705 ns/op       1.391 elapsed/op
GO/test/benchmark/zoo.lox-8                    10 3097766238 ns/op       3.134 elapsed/op
JAVA/test/benchmark/zoo.lox-8                   9 3355564380 ns/op       2.831 elapsed/op
PASS
ok   github.com/leonardinius/golox/test 1144.323s

Please find benchmark code here.