> Aztec.nr API reference, v6.0.0 (mainnet and testnet). Index: https://docs.aztec.network/aztec-nr-api/v6.0.0/llms.txt

# Module expr

Module: `std::meta::expr`

Contains methods on the built-in `Expr` type for quoted, syntactically valid expressions.

## Structs

- [AssertEqExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.AssertEqExpression.md): An assert-eq expression decomposed by [`Expr::as_assert_eq`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_assert_eq).
- [AssertExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.AssertExpression.md): An assert expression decomposed by [`Expr::as_assert`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_assert) into its predicate and optional message.
- [AssignExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.AssignExpression.md): An assignment expression decomposed by [`Expr::as_assign`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_assign).
- [BinaryOpExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.BinaryOpExpression.md): A binary operation decomposed by [`Expr::as_binary_op`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_binary_op).
- [CastExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.CastExpression.md): A cast expression decomposed by [`Expr::as_cast`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_cast).
- [ConstructorExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.ConstructorExpression.md): A constructor expression decomposed by [`Expr::as_constructor`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_constructor).
- [ConstructorField](/aztec-nr-api/v6.0.0/std/meta/expr/struct.ConstructorField.md): A field in a [`ConstructorExpression`](/aztec-nr-api/v6.0.0/std/meta/expr/struct.ConstructorExpression.md).
- [ForExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.ForExpression.md): A for loop over an expression, decomposed by [`Expr::as_for`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_for).
- [ForRangeExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.ForRangeExpression.md): A for loop over a range, decomposed by [`Expr::as_for_range`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_for_range).
- [FunctionCallExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.FunctionCallExpression.md): A function call decomposed by [`Expr::as_function_call`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_function_call).
- [IfExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.IfExpression.md): An if expression decomposed by [`Expr::as_if`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_if).
- [IndexExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.IndexExpression.md): An index expression decomposed by [`Expr::as_index`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_index).
- [IntegerLiteral](/aztec-nr-api/v6.0.0/std/meta/expr/struct.IntegerLiteral.md): An integer literal decomposed by [`Expr::as_integer`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_integer).
- [LambdaExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.LambdaExpression.md): A lambda expression decomposed by [`Expr::as_lambda`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_lambda).
- [LambdaParameter](/aztec-nr-api/v6.0.0/std/meta/expr/struct.LambdaParameter.md): A parameter in a [`LambdaExpression`](/aztec-nr-api/v6.0.0/std/meta/expr/struct.LambdaExpression.md).
- [LetExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.LetExpression.md): A let expression decomposed by [`Expr::as_let`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_let).
- [MemberAccessExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.MemberAccessExpression.md): A member access decomposed by [`Expr::as_member_access`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_member_access).
- [MethodCallExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.MethodCallExpression.md): A method call decomposed by [`Expr::as_method_call`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_method_call).
- [RepeatedElementArrayExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.RepeatedElementArrayExpression.md): A repeated-element array decomposed by [`Expr::as_repeated_element_array`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_repeated_element_array).
- [RepeatedElementVectorExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.RepeatedElementVectorExpression.md): A repeated-element vector decomposed by [`Expr::as_repeated_element_vector`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_repeated_element_vector).
- [UnaryOpExpression](/aztec-nr-api/v6.0.0/std/meta/expr/struct.UnaryOpExpression.md): A unary operation decomposed by [`Expr::as_unary_op`](/aztec-nr-api/v6.0.0/std/primitive.Expr.md#as_unary_op).