String Format

StringFormatExpression represents a string.Format call within an expression tree. It accepts a format string and an array of argument expressions, producing a string result equivalent to:

string.Format( format, arg0, arg1, ... )

An optional IFormatProvider expression is supported for culture-sensitive formatting.

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Factory Methods

using static Hyperbee.Expressions.ExpressionExtensions;

Overload	Description
StringFormat( Expression format, Expression argument )	Single argument
StringFormat( Expression format, Expression[] arguments )	Multiple arguments
StringFormat( Expression formatProvider, Expression format, Expression[] arguments )	With format provider

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Usage

Single Argument

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

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

var expr = Block(
    [value],
    Assign( value, Constant( 42 ) ),
    StringFormat( Constant( "The answer is {0}" ), value )
);

var lambda = Lambda<Func<string>>( expr );
Console.WriteLine( lambda.Compile()() );  // "The answer is 42"

Multiple Arguments

var name = Constant( "world" );
var count = Constant( 3 );

var formatExpr = StringFormat(
    Constant( "Hello, {0}! You have {1} messages." ),
    [name, count]
);

With Format Provider

var price = Constant( 9.99m );
var culture = Constant( System.Globalization.CultureInfo.GetCultureInfo("en-GB") );

var formatExpr = StringFormat(
    culture,
    Constant( "{0:C}" ),
    [price]
);
// produces "GBP9.99"

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Type

StringFormatExpression.Type is always typeof(string).

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Notes

• The format expression must produce a string value.
• Arguments are boxed to object[] internally, matching the string.Format signature.
• For simple concatenation, prefer Expression.Add on strings for better performance.
• For interpolated string patterns, StringFormat is the idiomatic approach in expression trees.