agent-framework/dotnet/src/Microsoft.Agents.AI.Workflows.Declarative/CodeGen/ForeachTemplate.tt

<#@ template language="C#" inherits="ActionTemplate" visibility="internal" linePragmas="false" #>
<#@ output extension=".cs" #>
<#@ assembly name="System.Core" #>
<#@ import namespace="Microsoft.Agents.ObjectModel" #>
<#@ include file="Snippets/AssignVariableTemplate.tt" once="true" #>
<#@ include file="Snippets/EvaluateValueExpressionTemplate.tt" once="true" #>
/// <summary>
/// Loops over a list assignign the loop variable to "<#= this.Model.Value #>" variable.
/// </summary>
internal sealed class <#= this.Name #>Executor(FormulaSession session) : ActionExecutor(id: "<#= this.Id #>", session)
{
    private int _index;
    private object[] _values = [];

    public bool HasValue { get; private set; }

    // <inheritdoc />
    protected override async ValueTask<object?> ExecuteAsync(IWorkflowContext context, CancellationToken cancellationToken)
    {
        this._index = 0;<#

        EvaluateValueExpression(this.Model.Items, "evaluatedValue");#>

        if (evaluatedValue == null)
        {
            this._values = [];
            this.HasValue = false;
        }
        else
        if (evaluatedValue is IEnumerable evaluatedList)
        {
            this._values = [.. evaluatedList];
        }
        else
        {
            this._values = [evaluatedValue];
        }

        await this.ResetAsync(context, null, cancellationToken).ConfigureAwait(false);

        return default;
    }

    public async ValueTask TakeNextAsync(IWorkflowContext context, object? _, CancellationToken cancellationToken)
    {
        if (this.HasValue = this._index < this._values.Length)
        {
            object value = this._values[this._index];
            <# 
            AssignVariable(this.Value, "value", tightFormat: true);

            if (this.Index is not null)
            {
                AssignVariable(this.Index, "this._index", tightFormat: true);
            }
            #>

            this._index++;
        }
    }

    public async ValueTask ResetAsync(IWorkflowContext context, object? _, CancellationToken cancellationToken)
    {<# 
        AssignVariable(this.Value, "UnassignedValue.Instance", tightFormat: true);

        if (this.Index is not null)
        {
            AssignVariable(this.Index, "UnassignedValue.Instance", tightFormat: true);
        }
      #>
    }
}