While

WhileExpression represents a while loop that repeats its body as long as a condition is true. It generates standard loop IL equivalent to:

while ( test )
    body;

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Factory Methods

using static Hyperbee.Expressions.ExpressionExtensions;

Overload	Description
While( Expression test, Expression body )	Basic while loop
While( Expression test, Expression body, LabelTarget brk, LabelTarget cont )	With explicit break/continue labels
While( Expression test, LoopBody body )	Body receives break/continue labels

The LoopBody delegate provides break and continue labels to the body builder:

public delegate Expression LoopBody( LabelTarget breakLabel, LabelTarget continueLabel );

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Usage

Basic While Loop

using static System.Linq.Expressions.Expression;
using static Hyperbee.Expressions.ExpressionExtensions;

var i = Variable( typeof(int), "i" );
var sum = Variable( typeof(int), "sum" );

var whileExpr = Block(
    [i, sum],
    Assign( i, Constant( 0 ) ),
    Assign( sum, Constant( 0 ) ),
    While(
        LessThan( i, Constant( 5 ) ),    // condition: i < 5
        Block(
            AddAssign( sum, i ),          // sum += i
            PostIncrementAssign( i )      // i++
        )
    ),
    sum
);

var lambda = Lambda<Func<int>>( whileExpr );
var fn = lambda.Compile();
Console.WriteLine( fn() );  // 10

While with Break

var i = Variable( typeof(int), "i" );

var whileExpr = Block(
    [i],
    Assign( i, Constant( 0 ) ),
    While(
        Constant( true ),                            // infinite loop
        ( brk, cont ) => Block(
            PostIncrementAssign( i ),
            IfThen(
                GreaterThanOrEqual( i, Constant( 5 ) ),
                Break( brk )                         // exit when i >= 5
            )
        )
    ),
    i
);

While with Continue

var i = Variable( typeof(int), "i" );

var whileExpr = Block(
    [i],
    Assign( i, Constant( 0 ) ),
    While(
        LessThan( i, Constant( 10 ) ),
        ( brk, cont ) => Block(
            PostIncrementAssign( i ),
            IfThen(
                Equal( Modulo( i, Constant( 2 ) ), Constant( 0 ) ),
                Continue( cont )                     // skip even numbers
            ),
            Call( typeof(Console).GetMethod("WriteLine", [typeof(int)]), i )
        )
    )
);

Inside an Async Block

var running = Variable( typeof(bool), "running" );

var asyncBlock = BlockAsync(
    [running],
    Assign( running, Constant( true ) ),
    While(
        running,
        Block(
            Await( Call( typeof(Task).GetMethod("Delay", [typeof(int)]), Constant( 100 ) ) ),
            Assign( running, Call( typeof(MyService).GetMethod("ShouldContinue") ) )
        )
    )
);

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Notes

• Pass Constant( true ) as test to create an infinite loop – use Break in the body to exit.
• The LoopBody delegate overloads are the idiomatic way to use Break and Continue without manually creating labels.
• See For and ForEach for other loop expressions.