E.g. while loop not working

[PallHaraldsson]

E.g. what doesn't work (and predictably "unexpected EOF while parsing" with one line shorter, and different error with, from the original, "while True:" ..):

julia> py2jl"""
       def __BOND_repl():
           SENTINEL = 1
           while SENTINEL>1:
             SENTINEL = 2
       """
ERROR: LoadError: "class: Compare, attributes: Symbol[:left, :comparators, :class, :lineno, :colno, :ops]."
Stacktrace:
 [1] (::getfield(Py2Jl.ASTGen, Symbol("##12#122")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}}})(::Dict{Symbol,Any}) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:392
 [2] ##Py2Jl.ASTGen 90#478 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:282 [inlined]
 [3] #12 at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:282 [inlined]
 [4] (::getfield(Py2Jl.ASTGen, Symbol("##12#122")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [5] (::getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}})(::Array{Dict{Symbol,Any},1}) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:187
 [6] macro expansion at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:240 [inlined]
 [7] ##Py2Jl.ASTGen 124#512 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:229 [inlined]
 [8] (::getfield(Py2Jl.ASTGen, Symbol("###Py2Jl.ASTGen 124#512#152")){String,Dict{Symbol,Any},getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [9] (::getfield(Py2Jl.ASTGen, Symbol("##12#122")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [10] (::getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}})(::Array{Dict{Symbol,Any},1}) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:187
 [11] ##Py2Jl.ASTGen 156#544 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:197 [inlined]
 [12] #12 at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:197 [inlined]
 [13] (::getfield(Py2Jl.ASTGen, Symbol("##12#122")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#121")){getfield(Py2Jl.ASTGen, Symbol("##7#114")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [14] to_ast(::Nothing, ::Dict{Symbol,Any}) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/ASTGen.jl:398
 [15] py2jl(::Nothing, ::String) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/Py2Jl.jl:43
 [16] @py2jl_str(::LineNumberNode, ::Module, ::Any) at /home/qwerty/.julia/packages/Py2Jl/G6hOG/src/Py2Jl.jl:51
in expression starting at REPL[5]:1

[thautwarm]

Wait for several minutes. I'm going out for some food.

[thautwarm]

That's not caused by while, instead of compare...

[thautwarm]

Updated , check if resolved?

[PallHaraldsson]

Yes, forks (checked in 1.1.0), while not for "True" (not too important for me I think, I can work around):

julia> py2jl"""
              def __BOND_repl():
                  SENTINEL = 1
                  while True:
                    SENTINEL = 2
              """
Dict{Symbol,Any}
ERROR: LoadError: "class: NameConstant, attributes: Symbol[:value, :class, :lineno, :colno]."
Stacktrace:
 [1] (::getfield(Py2Jl.ASTGen, Symbol("##12#131")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}}})(::Dict{Symbol,Any}) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:440
 [2] ##Py2Jl.ASTGen 108#473 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:312 [inlined]
 [3] #12 at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:312 [inlined]
 [4] (::getfield(Py2Jl.ASTGen, Symbol("##12#131")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [5] (::getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}})(::Array{Dict{Symbol,Any},1}) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:217
 [6] macro expansion at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:270 [inlined]
 [7] ##Py2Jl.ASTGen 142#507 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:259 [inlined]
 [8] (::getfield(Py2Jl.ASTGen, Symbol("###Py2Jl.ASTGen 142#507#161")){String,Dict{Symbol,Any},getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [9] (::getfield(Py2Jl.ASTGen, Symbol("##12#131")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [10] (::getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}})(::Array{Dict{Symbol,Any},1}) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:217
 [11] ##Py2Jl.ASTGen 174#539 at /home/qwerty/.julia/packages/MLStyle/ksIXg/src/MLStyle.jl:227 [inlined]
 [12] #12 at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:227 [inlined]
 [13] (::getfield(Py2Jl.ASTGen, Symbol("##12#131")){Nothing,getfield(Py2Jl.ASTGen, Symbol("#trans_block#130")){getfield(Py2Jl.ASTGen, Symbol("##7#123")){Nothing}}})(::Dict{Symbol,Any}) at ./none:0
 [14] to_ast(::Nothing, ::Dict{Symbol,Any}) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/ASTGen.jl:450
 [15] py2jl(::Nothing, ::String) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/Py2Jl.jl:43
 [16] @py2jl_str(::LineNumberNode, ::Module, ::Any) at /home/qwerty/.julia/packages/Py2Jl/LUvcL/src/Py2Jl.jl:51
in expression starting at REPL[4]:1

FYI. I'll look more at your package, but even though abandoned, I will try out too https://github.com/TotalVerb/PythonSyntax.jl

It's not a substitute, while in a way if it supports more syntax, but I'll look at it at least for fun, and maybe there's something of value to know there?

[thautwarm]

Okay, in fact you can check https://github.com/python/cpython/blob/master/Parser/Python.asdl to see what I haven't implemented yet.

[thautwarm]

To support True, firstly we search which role the True performs in Python ASDL.

In Python 3.8+, True is stored in Constant,
https://github.com/python/cpython/blob/master/Parser/Python.asdl#L81

| Constant(constant value, string? kind)

in other Python 3.x versions, it's a NameConstant:
https://github.com/python/cpython/blob/afe3a4975cf93c97e5d6eb8800e48f368011d37a/Parser/Python.asdl#L75

| NameConstant(singleton value)

And you can install astpretty in PyPI to check what is the AST for specific codes:

Python 3.7.3 (default, Mar 27 2019, 22:11:17) 
Type 'copyright', 'credits' or 'license' for more information
IPython 7.6.1 -- An enhanced Interactive Python. Type '?' for help.

> from ast import parse as p
> from astpretty import pprint as pp
> def ppp(x): pp(p(x))
> ppp("True")
Module(
    body=[
        Expr(
            lineno=1,
            col_offset=0,
            value=NameConstant(lineno=1, col_offset=0, value=True),
        ),
    ],
)

Then it'll be translated into such a json in Py2Jl.jl:

Dict(
   :class => "Module", 
   :body =>  [
            Dict(:value =>
                   Dict(:value => true,
                          :class => "NameConstant",
                          :lineno => 1,
                          :colno => 0
                   ),
                :class => "Expr",
                :lineno => 1,
                :colno => 0)
])

I then make a translation for such a Python 3.7 AST of True by adding such a block at
https://github.com/JuliaCN/Py2Jl.jl/blob/master/src/ASTGen.jl#L420

Record(:class => "NameConstant", value) -> value

In fact for Python 3.8+ , the way to support True is almost the same:

Record(:class => "Constant", value) -> value

Then I add a corresponding test:

py2jl"""
def __BOND_repl():
        SENTINEL = 10
        while True:
            break
        return SENTINEL
    """
    @testset "True" begin
            @test __BOND_repl() == 10
    end
end

[thautwarm]

That's quite simple, isn't it?
Gonna sleep, wouldn't reply in 12 hrs.

[PallHaraldsson]

I thought I should let you know (and also that 1.2.0-rc3 is out):

I saw in PR 31882 at Julia:
"LoadError is deprecated because it is no longer emitted by the runtime as of Julia 1.3."

I never really found out why "LoadError" was happening. or was sure what it means in general. I may look more into there there (or here). [I didn't want to put in a link here, only the number, in case it makes a link and distracts discussion there. So you have to copy paste to see the PR.]

[thautwarm]

I just throw the message out.