dansanderson
commented
2 years ago For anyone looking for this feature, there's now a partial solution: luamin supports a --keep-names-from-file=<filename> argument that takes a list of names from a text file and preserves those names while renaming others. There's also a --keep-all-names flag.
I'm currently thinking that the best solution to the property (attribute) renaming edge case is for the name list to support patterns. That way code that uses both var.prop1 and var["prop" + n] could just add prop* to the name list. I think this is better than a flag that preserves all attribute names. It requires the developer to be explicit about which names to exempt, but captures the major use cases of dynamic attribute indexing that I can think of.
luamin renames not only names of variables but also names of properties of objects stored in variables referenced with dot syntax:
var.propmight becomea.b. In Lua, it is also possible to refer to a property with indexing syntax, where the property name is a runtime expression:var["prop"], or evenvar["pr" + x]. When a PICO-8 cart uses both dot syntax and indexing syntax to refer to the same property, when luamin renames the dot syntax is breaks the runtime indexing. There's no way to programmatically transform the indexing code to work with the new name.It is rare (and, IMO, poor style) for Lua code to use both dot syntax and indexing syntax for the same property, but it can be useful in some PICO-8 applications. Carts that use this technique need property renaming disabled, at least for the specific properties referred to both ways. luamin could just never rename properties to solve for this edge case, but at the significant expense of carts that only refer to a property with dot syntax:
var.some_long_prop_namebecomesa.some_long_prop_name.The next best thing would be to allow the user to disable property renaming with a flag to the tool:
p8tool luamin --no-rename-properties foo.p8(This was proposed in PR 54 as aluamin2variation, though it works better as a flag.) This might be the most practical solution.A refinement might be to allow the user to provide a list of property name patterns to preserve (because the indexing technique is most useful for property names that conform to a pattern), either as an external file or with tool hints in the source itself:
-- @proppattern elem\d+would preservex.elem1,abc.elem987, etc. and allow forx["elem" + n].It is provably impossible to detect when indexing a variable would refer to a specific property in all cases. Consider:
x.prop = 1; y = x; y.prop = 2Or:x.prop = 1; y.obj = x; z = "obj"; y[z]["prop"] = 2It may be possible to detect some simpler cases, such as indexing only used with constant expressions. I doubt this would be worth the effort for PICO-8 applications.