# Debugging in Juno constantly stops in low-level functions

**URL:** <https://discourse.julialang.org/t/debugging-in-juno-constantly-stops-in-low-level-functions/52915>\
**Category:** Juno\
**Tags:** debug\
**Created:** [January 6, 2021, 2:35am UTC](https://discourse.julialang.org/t/debugging-in-juno-constantly-stops-in-low-level-functions/52915 "2021-01-06T02:35:47Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![boranzhao](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/boranzhao/32/20802_2.png) [@boranzhao](https://discourse.julialang.org/u/boranzhao)\
**Post date:** [January 6, 2021, 2:35am UTC](https://discourse.julialang.org/t/debugging-in-juno-constantly-stops-in-low-level-functions/52915/1 "2021-01-06T02:35:47Z")

</div>

Hello,

I am a new user of Julia and Juno. I created a nonlinear optimization problem using JuMP, which uses nonlinear expressions and constraints. I tried to debug my code using the Debugger in Juno. However, when I clicked “continue” or “next line” around the following lines,

```julia
        @constraint(MPC,X[i][1]+h*X[i][4] == X[i+1][1]);
        @constraint(MPC,X[i][2]+h*X[i][5] == X[i+1][2]);
        @constraint(MPC,X[i][3]+h*X[i][6] == X[i+1][3]);

```

the cursor constantly entered the function “rewrite\_and\_return” in the “rewrite.jl” file, and the function “\_constraint\_macro” in “macros.jl” file; keep clicking “next line” will move the cursor out of the two files back to my code. I could not understand why clicking “continue” or “next line” brought the cursor to those low-level files.

Thank you for your help.

Best  
Pan