Struct Expr 

pub struct Expr;

Fluent builder for constructing expression trees

Provides a convenient API for building complex expressions without excessive nesting of Box::new() calls.

Example

use solverforge_core::wasm::{Expression, Expr};
use solverforge_core::wasm::FieldAccessExt;

// Build: param(0).employee != null
let shift = Expr::param(0);
let employee = shift.get("Shift", "employee");
let predicate = Expr::is_not_null(employee);

Implementations

impl Expr

pub fn int(value: i64) -> Expression

Create an integer literal (compiles to i32)

pub fn int64(value: i64) -> Expression

Create a 64-bit integer literal (compiles directly to i64) Use for datetime arithmetic and other i64 operations.

pub fn bool(value: bool) -> Expression

Create a boolean literal

pub fn null() -> Expression

Create a null literal

pub fn param(index: u32) -> Expression

Access a function parameter by index

pub fn eq(left: Expression, right: Expression) -> Expression

Equal comparison (==)

pub fn ne(left: Expression, right: Expression) -> Expression

Not equal comparison (!=)

pub fn lt(left: Expression, right: Expression) -> Expression

Less than comparison (<)

pub fn le(left: Expression, right: Expression) -> Expression

Less than or equal comparison (<=)

pub fn gt(left: Expression, right: Expression) -> Expression

Greater than comparison (>)

pub fn ge(left: Expression, right: Expression) -> Expression

Greater than or equal comparison (>=)

pub fn eq64(left: Expression, right: Expression) -> Expression

Equal comparison for i64 (==)

pub fn ne64(left: Expression, right: Expression) -> Expression

Not equal comparison for i64 (!=)

pub fn lt64(left: Expression, right: Expression) -> Expression

Less than comparison for i64 (<)

pub fn le64(left: Expression, right: Expression) -> Expression

Less than or equal comparison for i64 (<=)

pub fn gt64(left: Expression, right: Expression) -> Expression

Greater than comparison for i64 (>)

pub fn ge64(left: Expression, right: Expression) -> Expression

Greater than or equal comparison for i64 (>=)

pub fn and(left: Expression, right: Expression) -> Expression

Logical AND (&&)

pub fn or(left: Expression, right: Expression) -> Expression

Logical OR (||)

pub fn not(operand: Expression) -> Expression

Logical NOT (!)

pub fn is_null(operand: Expression) -> Expression

Null check (is null)

pub fn is_not_null(operand: Expression) -> Expression

Not-null check (is not null)

pub fn add(left: Expression, right: Expression) -> Expression

Addition (+)

pub fn sub(left: Expression, right: Expression) -> Expression

Subtraction (-)

pub fn mul(left: Expression, right: Expression) -> Expression

Multiplication (*)

pub fn div(left: Expression, right: Expression) -> Expression

Division (/)

pub fn add64(left: Expression, right: Expression) -> Expression

Addition for i64 (+)

pub fn sub64(left: Expression, right: Expression) -> Expression

Subtraction for i64 (-)

pub fn mul64(left: Expression, right: Expression) -> Expression

Multiplication for i64 (*)

pub fn div64(left: Expression, right: Expression) -> Expression

Division for i64 (/)

pub fn host_call( function_name: impl Into<String>, args: Vec<Expression>, ) -> Expression

Call a host function

pub fn list_contains(list: Expression, element: Expression) -> Expression

Check if a list contains an element

Generates a loop that iterates through the list and checks for equality. Returns true if the element is found, false otherwise.

pub fn string_equals(left: Expression, right: Expression) -> Expression

String equality via host function

Equivalent to: hstringEquals(left, right)

pub fn ranges_overlap( start1: Expression, end1: Expression, start2: Expression, end2: Expression, ) -> Expression

Check if two time ranges overlap (i32 version)

Equivalent to: start1 < end2 && start2 < end1

pub fn ranges_overlap64( start1: Expression, end1: Expression, start2: Expression, end2: Expression, ) -> Expression

Check if two time ranges overlap (i64 version for datetime)

Equivalent to: start1 < end2 && start2 < end1 Use this for datetime fields stored as i64.

pub fn if_then_else( condition: Expression, then_branch: Expression, else_branch: Expression, ) -> Expression

If-then-else conditional expression (produces i32)

pub fn if_then_else64( condition: Expression, then_branch: Expression, else_branch: Expression, ) -> Expression

If-then-else conditional expression (produces i64) Use for datetime arithmetic where branches return i64 values.

pub fn i64_to_i32(operand: Expression) -> Expression

Wrap i64 to i32 (truncate) Use to convert i64 arithmetic results to i32 for final comparisons.

pub fn i32_to_i64(operand: Expression) -> Expression

Extend i32 to i64 (signed) Use to convert i32 values (like date epoch days) to i64 for datetime arithmetic.