# VsCode julia execute file and while loop
**URL:** https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022
**Category:** Tooling
**Created:** [December 18, 2020, 3:20am UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022 "2020-12-18T03:20:45Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@hei06j](https://discourse.julialang.org/u/hei06j)
#### Post date: [December 18, 2020, 3:20am UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022/1 "2020-12-18T03:20:45Z")
Hi,
I have a script with a while loop. When I run the code using “Shift+Enter”, “Alt+Enter” or even “Execute Code” everything is fine. But when I use “Execute file”, two errors I get (1) the global variables are not recognised inside the while loop, (2) it cannot exit the while loop.
I appreciate any advice.
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### Author:  [@josePereiro](https://discourse.julialang.org/u/josePereiro)
#### Post date: [December 18, 2020, 5:38am UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022/2 "2020-12-18T05:38:32Z")
Hi, could you provide an example of your code?
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### Author:  [@r2cp](https://discourse.julialang.org/u/r2cp)
#### Post date: [December 18, 2020, 1:01pm UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022/3 "2020-12-18T13:01:36Z")
My guess is that you mean what’s discussed here (minute 20:30). Hope it helps.
[https://youtu.be/xKrIp4ZVOrg](https://youtu.be/xKrIp4ZVOrg)
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### Author:  [@hei06j](https://discourse.julialang.org/u/hei06j)
#### Post date: [December 23, 2020, 12:04am UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022/4 "2020-12-23T00:04:16Z")
> Thanks for the rely. Below is the code, either loop can be safely commented out. In the first loop it does not recognise kWsum, and in the second loop, it just gets stuck.
```julia
using Pkg
Pkg.activate(pwd())
Pkg.add("OpenDSSDirect")
using OpenDSSDirect
dss("""
Clear
New Circuit.Kersting_nr_LineGeometry_Balanced phases=3 basekv=12.47 bus1=B1 MVASC1=1e8 MVASC3=1e8
New Wiredata.Hawk DIAM=0.858 GMR=0.029 RAC=0.216
~ NormAmps=530 // this param is not defined
~ Runits=mi radunits=in gmrunits=ft
New Linegeometry.OverHead1 nconds=4 nphases=3
~ cond=1 Wire=Hawk x=-48 h=348 units=in
~ cond=2 Wire=Hawk x=-21 h=348 units=in
~ cond=3 Wire=Hawk x=40 h=348 units=in
~ cond=4 Wire=Hawk x=0 h=286 units=in // h is not defined
New Line.Line1 bus1=B1.1.2.3.0 bus2=B2.1.2.3.4
~ Geometry=OverHead1
~ Length=1.893939 units=mi
~ EarthModel=Carson
New Reactor.grounding phases=1 bus1=B1.4 bus2=B1.0 R=100 X=0.01
New Load.LoadP1 phases=1 bus1=B2.1.4 kv=12.47 model=1 conn=wye kVA=3000 pf=0.9 vminpu=0.1 vmaxpu=2
New Load.LoadP2 phases=1 bus1=B2.2.4 kv=12.47 model=1 conn=wye kVA=3000 pf=0.9 vminpu=0.1 vmaxpu=2
New Load.LoadP3 phases=1 bus1=B2.3.4 kv=12.47 model=1 conn=wye kVA=3000 pf=0.9 vminpu=0.1 vmaxpu=2
Set Toler=0.00000001
Solve
""")
solution = Dict{String,Any}()
# load power
solution["load"] = Dict{String,Any}()
loadnumber = Loads.First()
kWsum = 0.0
kvarsum = 0.0
while loadnumber > 0
load_name = Loads.Name()
solution["load"][load_name] = Dict{String,Any}()
solution["load"][load_name]["pd"] = Loads.kW()
solution["load"][load_name]["qd"] = Loads.kvar()
kWsum += Loads.kW()
kvarsum += Loads.kvar()
loadnumber = Loads.Next()
end
# line currents
solution["line"] = Dict{String,Any}()
linenumber = PDElements.First()
while linenumber > 0
name = PDElements.Name()
Circuit.SetActiveElement(name)
if split(name,".")[1] == "Line"
line_name = split(name,".")[2]
@show line_name
solution["line"][line_name] = Dict{String,Any}()
solution["line"][line_name]["bus_fr"] = Lines.Bus1()
solution["line"][line_name]["bus_to"] = Lines.Bus2()
solution["line"][line_name]["nphases"] = Lines.Phases()
solution["line"][line_name]["linecode"] = Lines.LineCode()
solution["line"][line_name]["zmatrix"] = Lines.ZMatrix()
solution["line"][line_name]["length"] = Lines.Length()
solution["line"][line_name]["unit"] = Lines.Units()
solution["line"][line_name]["c"] = PDElements.AllCurrentsAllCurrents()[1:Lines.Phases()]
end
linenumber = PDElements.Next()
end
```
---
### Author:  [@josePereiro](https://discourse.julialang.org/u/josePereiro)
#### Post date: [December 25, 2020, 4:38am UTC](https://discourse.julialang.org/t/vscode-julia-execute-file-and-while-loop/52022/5 "2020-12-25T04:38:07Z")
This is expected, you defined `kWsum` in a global [scope](https://www.google.com/search?q=julia+scope&rlz=1C5CHFA_enAE836AE836&oq=julia+scope&aqs=chrome..69i57j35i19i39j46l2j0j69i60l3.2326j0j7&sourceid=chrome&ie=UTF-8), but the for loop will create its own local variable `kWsum` by default unless you make it explicitly `global`. This may look like a weird design decision, but it’s intended to reduce the risk of affecting unintentionally a distant `global` variable.
You are doing this.
```julia
var = 1.0 # global
for i in 1:10
var += 1 # uninitialized new local
end
println(var)
# ERROR: LoadError: UndefVarError: var not defined
# Stacktrace:
# [...]
```
To solve this the general advice, I think, is to grab all your code in a function (which introduce a `local` scope). This also have many other advantages ([performance](https://docs.julialang.org/en/v1/manual/performance-tips/#Avoid-global-variables) included). But if you wanna work in the `global` scope anyway you can do
```julia
var = 1.0 # global
for i in 1:10
global var += 1 # reusing global
end
println(var)
# 11.0
```
But to understand better I recommend you to read the [manual](https://docs.julialang.org/en/v1/manual/variables-and-scoping/#scope-of-variables) and do a couple of examples.