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Frontmatter

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Author 1

Reactive Python

The pyr" macro is just like the py" macro from PyCall.jl, except it is reactive! This means:

  • If you define a Python variable, then other cells that use that python variable are also evaluated.

  • The scope of Python variables is cleaned up automatically.

  • Multiple definitions are not allowed.

This is using the Python port of Pluto.ExpressionExplorer by Mikołaj Bochenski: https://github.com/lightning-notebook/engine and some Julia macro magic.

👀 Reading hidden code
39.1 ms
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pyr"""
y = x + x
"""
163 ms
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pyr"""
x = 2
"""
470 μs
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pyr"[x, y]"
20.6 ms
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pyr"""
def cool(x, y):
return 123123
"""
705 μs
123123
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pyr"cool(x, x)"
1.4 ms
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using PyCall
1.5 s
import Pkg
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166 μs
# Pkg.build("PyCall")
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8.0 μs
0.9092974268256817
begin
py"""
import math
math.sin
"""
py"math.sin"(2)
end
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18.8 ms
Error message

MethodError: objects of type Nothing are not callable

Stack trace

Here is what happened, the most recent locations are first:

  1. from This cell: line 2
    begin	py"""	import math
uhmmmmmm??!
begin
py"""
import math
math.sin"""(2)
end
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---
using PlutoUI
👀 Reading hidden code
146 ms
Expr
  head: Symbol macrocall
  args: Array{Any}((3,))
    1: Symbol @py_str
    2: LineNumberNode
      line: Int64 1
      file: Symbol /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#6449e96f-19ce-4100-8b35-56113bc24b7d
    3: String "[1+1]"
Dump(:(py"[1+1]"))
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3.6 ms
Expr
  head: Symbol macrocall
  args: Array{Any}((3,))
    1: Symbol @py_str
    2: LineNumberNode
      line: Int64 1
      file: Symbol /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#d9bc5dc1-67b6-47c6-9592-3b474ec451a0
    3: String "[1+1]\n"
Dump(:(py"""
[1+1]
"""))
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120 μs
rw = py_reads_writes("x=2")
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121 ms
rw[2] |> collect
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11.8 ms
quote
    #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:8 =#
    begin
        #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:12 =#
        let s = var"py#var_b"
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:13 =#
            begin
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:25 =#
                var"#471#m" = Main.workspace#4.pynamespace(Main.workspace#4.Main)
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:26 =#
                begin
                    var"#471#m"["__julia_localvar_25_1"] = Main.workspace#4.PyObject(s)
                end
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:27 =#
                var"#472#ret" = (PyAny)(Main.workspace#4.pyeval_(Base.string("b = __julia_localvar_25_1\n"), var"#471#m", var"#471#m", 257, "/home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa"))
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:28 =#
                nothing
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:29 =#
                var"#472#ret"
            end
        end
    end
    #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:19 =#
    var"#470#output" = begin
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:25 =#
            var"#473#m" = Main.workspace#4.pynamespace(Main.workspace#4.Main)
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:26 =#
            begin
            end
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:27 =#
            var"#474#ret" = (PyAny)(Main.workspace#4.pyeval_((Main.workspace#5.Base).string("x = 123\ny = b\n"), var"#473#m", var"#473#m", 257, "/home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa"))
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:28 =#
            nothing
            #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:29 =#
            var"#474#ret"
        end
    #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:23 =#
    begin
        #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:27 =#
        var"py#var_x" = begin
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:25 =#
                var"#475#m" = Main.workspace#4.pynamespace(Main.workspace#4.Main)
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:26 =#
                begin
                end
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:27 =#
                var"#476#ret" = (PyAny)(Main.workspace#4.pyeval_(Base.string("x"), var"#475#m", var"#475#m", 258, "/home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa"))
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:28 =#
                begin
                end
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:29 =#
                var"#476#ret"
            end
    end
    begin
        #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:27 =#
        var"py#var_y" = begin
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:25 =#
                var"#477#m" = Main.workspace#4.pynamespace(Main.workspace#4.Main)
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:26 =#
                begin
                end
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:27 =#
                var"#478#ret" = (PyAny)(Main.workspace#4.pyeval_(Base.string("y"), var"#477#m", var"#477#m", 258, "/home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa"))
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:28 =#
                begin
                end
                #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#b9903477-5070-43eb-82a9-8b750f79c8fa:29 =#
                var"#478#ret"
            end
    end
    #= /home/runner/work/disorganised-mess/disorganised-mess/reactive python.jl#==#5c432b4e-60e0-4288-8d5a-42e364ce8d16:31 =#
    var"#470#output"
end
@macroexpand pyr"""
x = 123
y = b
"""
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725 μs
3
begin
custom_py"""
x = 3
"""

custom_py"x"
end
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28.3 ms
begin
rand(), try
var"#py_var_x"
catch end
end
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6.4 ms
123
123
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8.0 μs
1123124
pyr"f(1)"
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548 μs
pyr"""
def f(x):
return x + 1123123
"""
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632 μs
Error message

UndefVarError: @pyr_str not defined

Stack trace

Here is what happened, the most recent locations are first:

  1. from :0
  2. #macroexpand#51
    from expr.jl:117
  3. from This cell: line 1
    Base.remove_linenums!(Meta.macroexpand(@__MODULE__, :(pyr"""x = 123
Base.remove_linenums!(Meta.macroexpand(@__MODULE__, :(pyr"""
x = 123
y = b
"""); recursive=false))
👀 Reading hidden code
---
# string(Expr(:symbol, Symbol("#a")))
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8.6 μs
@pyr_str (macro with 1 method)
macro pyr_str(str)
var"@custom_py_str"
reads, writes = py_reads_writes(str)

quote
# if false
$([let
julia_s = Symbol("py#var_", py_s)
import_code = """$(py_s) = \$(s)\n"""
esc(quote
let s = $(julia_s) # for pluto to recognise
@custom_py_str($(import_code)) # load stored PyObject into python using that name
end
end)
end for py_s in reads]...)
# end
output = @custom_py_str($(str))
# if false

$([let
julia_s = Symbol("py#var_", py_s)
import_code = "$(py_s)"
esc(quote
$(julia_s) = @custom_py_str($(import_code)) # store PyObject as julia object, so that it can use Pluto's reactivity
end)
end for py_s in writes]...)
# end
output
end
end
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2.5 ms
@pyr_old_str (macro with 1 method)
macro pyr_old_str(str)
var"@custom_py_str"
reads, writes = py_reads_writes(str)

quote
if false
$([esc(:($(Symbol("#py", s)) = 1)) for s in writes]...)
$([esc(:($(Symbol("#py", s)))) for s in reads]...)
end
@custom_py_str($(str))
end
end
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1.9 ms
import PyCall: interpolate_pycode, Py_file_input, make_fname, Py_eval_input, pynamespace, pyeval_
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199 μs
2
custom_py"""
1 + 1"""
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285 ms
@custom_py_str (macro with 1 method)
macro custom_py_str(code, options...)
T = length(options) == 1 && 'o' in options[1] ? PyObject : PyAny
code, locals = interpolate_pycode(code)
input_type = '\n' in code ? Py_file_input : Py_eval_input
fname = make_fname(@__FILE__)
assignlocals = Expr(:block, [(isa(v,String) ?
:(m[$v] = PyObject($(esc(ex)))) :
nothing) for (v,ex) in locals]...)
code_expr = Expr(:call, esc(:(Base.string)))
i0 = firstindex(code)
for i in sort!(collect(filter(k -> isa(k,Integer), keys(locals))))
push!(code_expr.args, code[i0:prevind(code,i)], esc(locals[i]))
i0 = i
end
push!(code_expr.args, code[i0:lastindex(code)])
if input_type == Py_eval_input
removelocals = Expr(:block, [:(delete!(m, $v)) for v in keys(locals)]...)
else
# if we are evaluating multi-line input, then it is not
# safe to remove the local variables, because they might be referred
# to in Python function definitions etc. that will be called later.
removelocals = nothing
end
quote
m = pynamespace(Main)
$assignlocals
ret = $T(pyeval_($code_expr, m, m, $input_type, $fname))
$removelocals
ret
end
end
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4.7 ms

Following code is from https://github.com/lightning-notebook/engine/blob/master/tests/testvariableaccess.py

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17.0 ms
PyObject <function reads_writes at 0x7fd600fd87c0>
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432 ms