On Thu, Aug 11, 2016 at 6:40 AM, Andrei Zh <faithlessfri...@gmail.com> wrote:
> One more question related to the topic. I try to get function body > expression in Julia 0.5 using: > > lambda = methods(func, types).ms[1].lambda_template > Base.uncompressed_ast(lambda) > > However this gives an expression with argument names replaced by > `SlotNumber` (e.g. `_2`). Is there a way to get function expression with > actual variable names or a recommended way to convert `SlotNumbers` to it? > So far I've only found this piece of code > <https://github.com/JuliaDiff/ReverseDiffSource.jl/blob/master/src/frdiff.jl#L63-L76> > in ReverseDiffSource.jl, but the package is currently broken under Julia > 0.5, so I suppose there might be more stable way to do it. > `slotnames` of LambdaInfo should have what you want. Do note that the name is not unique. > > > On Monday, August 8, 2016 at 10:39:34 PM UTC+3, Andrei Zh wrote: >> >> Thanks, this makes sense. Just for clarification: >> >> >>> It strongly depend on what you want to do and whether you care about >>> what they represent. >>> >> >> I want to apply transformations (mostly) to algebraic expressions and >> function calls in order to simplify them, replace argument names, find >> derivatives, etc. Thus I don't really care about the difference between >> GlobalRef and dot notation as long as they contain the same amount of >> information and I can evaluate them to actual function objects. But since >> there's a choice between 2 options I was trying to understand which one is >> more suitable for me and whether I can cast one to another (again, in the >> context of my simple transformations). >> >> Now based on what you've told about optimization and >> `Base.uncompressed_ast()` I believe these 2 options - GloablRef and dot >> notation - are interchangeable for my use case. >> >> >>> The devdoc should have fairly complete description of what these nodes >>> are. >>> >> >> What they are - yes, but not when to use which one. Anyway, I didn't >> intend to abuse anyone, just tried to get my head around AST internals. >> >> >> >>> >>> >>>> >>>> >>>> >>>> On Monday, August 8, 2016 at 1:55:51 AM UTC+3, Yichao Yu wrote: >>>>> >>>>> >>>>> >>>>> On Mon, Aug 8, 2016 at 3:57 AM, Andrei Zh <faithle...@gmail.com> >>>>> wrote: >>>>> >>>>>> While parsing Julia expressions, I noticed that sometimes calls to >>>>>> >>>>> >>>>> This shouldn't happen. >>>>> >>>>> >>>>>> global functions resolve to `GloablRef` and sometimes to >>>>>> >>>>> >>>>> and GlobalRef should only happen during lowering. >>>>> >>>>> >>>>>> getfield(Module, func). Could somebody please clarify: >>>>>> >>>>>> 1. Why do we need both? >>>>>> >>>>> >>>>> GlobalRef is essentially an optimization. It's more restricted and >>>>> easier to interpret/codegen and is emitted by lowering/type inference when >>>>> it is legal to do so. >>>>> >>>>> >>>>>> 2. Is it safe to replace one by the other (assuming only modules and >>>>>> functions are involved)? >>>>>> >>>>> >>>>> Not always. There are certainly cases where a GlobalRef currently >>>>> can't be used (method definition for example) I'm not sure if there's >>>>> cases >>>>> the other way around. >>>>> >>>>> >>>
