microsoft / microsoft/AL

Bug in using "continue" in nested foreach loop

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Description

Please include the following with each issue:

1. Describe the bug
When using continue inside a foreach loop that resides within another loop, continue will step out of the inner foreach loop.
2. To Reproduce
Steps to reproduce the behavior:

  1. Go to '...'
codeunit 50000 "MyContinueTest"
{
    trigger OnRun()
    var
        List: List of [Code[1]];
        Item: Code[1];
        FieldNo: Integer;
        Nos: Integer;
    begin
        Nos := 5;
        List.Add('A');
        List.Add('B');
        List.Add('C');


        for FieldNo := 1 to Nos do begin
            if FieldNo = 3 then
                continue;
            foreach Item in List do
                if item = 'A' then
                    continue
                else
                    Message('Field No: %1 Processing item: %2', FieldNo,Item);
        end;
    end;
}

3. Expected behavior
In the example above I would expect message boxes with Fieldnos 1 to 3 and item B and C.

4. Actual behavior
I get no Message box at all!

5. Versions:

  • AL Language: 18.0.2732683
  • Visual Studio Code: 1.137.0
  • Business Central: 28.4
  • List of Visual Studio Code extensions that you have installed: Disabled
  • Operating System:
    • Windows
    • Linux
    • MacOS
Final Checklist

Please remember to do the following:

  • Search the issue repository to ensure you are reporting a new issue

  • Reproduce the issue after disabling all extensions except the AL Language extension

  • Simplify your code around the issue to better isolate the problem

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by running the provided AL codeunit reproduction with AL Language 18.0.2732683 and Business Central 28.4, then trace how nested foreach and continue are handled by the compiler or language extension. Done means continue skips only the current foreach iteration, producing messages for items B and C in the expected outer-loop iterations.

Written by the indexing model from the issue text.

Assessment

Domain
compilers, devtools
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Active
Clarity
Mostly clear
Newbie friendliness
55/100

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