I am pleased to announce the release of pytogo 1.2. https://gitlab.com/esr/pytogo
New features in this release: * PEP484 type hints are now converted into Go type signatures. * Without PEP484 hints, return types of functions are now sometimes deduced. * Docstrings are moved to the godoc-preferred position above the signature. * Python math and cmath library functions are mapped over. * Python shebang lines are recognized and converted to "package main". * Map variadic function signatures to use "..." * Import translation. Of these, the most interesting to go-nuts is almost certainly the PEP484 support. It means that function signatures can be type-annotated in context in Python before it is translated, substantially reducing the among of hand-fixing required in the generated Go code. While this is still not a perfect, fire-and-forget translator - and never will be - the ratio of output quality over LOC is, I feel, nothing short of astonishing. We get what Michael Ellis described as "a good first draft" from just just 594 lines of Python, much of that rule tables rather than code! This demonstrates very concretely that the semantic gap between Python and Go is narrow. The algorithm used for import translation is, though naive, surprisingly effective. Python "import foo" is moved straight to Go `import "foo"` (actually spans of them are grouped as is idiomatic in Go) except that there is a table of special cases that should be dropped or translated. So, for example, "import sys" is dropped (the portable stuff in it is in Go os package) but "cmath" is mapped to "math/cmplx". Because Go throws errors on unrecognized or unneeded imports, cleanup of an import section after translation is fast and easy. This program will undoubtedly continue to gain capability, simply because the overhead of adding new rules (such as new standard library module mappings) is very low and testing them is easy. One current development focus is better translation of "in" expressions outside for loops. It is also very likely that the next release will translate some module-level assignments in Python to Go var and const declarations. Sometimes minimum-effort, kludgy, brute-force-ish approaches work very well. Python-to-idiomatic-Go translation seems to be one of them. Not losing sight of the goal despite this yak-shaving. The reposurgeon translation is at 35% and my translation speed is up to more than 400 LOC per day, easily doubling what I was doing before. It would be faster still if I weren't writing a lot of unit tests that weren't there in the Python, and I expect it to continue to rise. I plan to ship my experience report on the translation to go-nuts at somewhere around 70%. It will be meaty. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
