Module expr 

Scalar expression evaluator: turns an Expr into a Value under a row context (column -> value) and a parameter binding.

Structs

CompiledLikePattern

A LIKE/ILIKE pattern compiled once for repeated evaluation.

EvalContext

Enums

IntegerWidth

Constants

NAMED_ARG_FUNCTION

Marker function the compiler wraps name => value call arguments in (NamedArgExpr has no dedicated AST node).

TO_HEX_INT4_FUNCTION

Physical scalar built-ins selected after PostgreSQL overload resolution has preserved the declared integer width.

TO_HEX_INT8_FUNCTION

Traits

EngineHook

Engine-side hook that scalar function evaluation calls for stateful sequence and user-defined functions. Query-valued expressions are not accepted here: lowering assigns them physical query-plan slots executed by uqa-execution::ScalarSubqueryRunner.

RowLookup

Read-only row interface used by the expression evaluator. Most callers use a materialised ResultRow, while hot execution paths can expose a projected value slice without rebuilding a string-keyed map for every row.

Functions

array_dimensions

Return every dimension of a rectangular array value.

array_value_to_string

builtin_scalar_function_strictness

Return the PostgreSQL 18 strictness contract for a built-in scalar call when its implemented overload is known.

cast_value

Cast a value to the named SQL type, mirroring CAST(expr AS ty). Types outside the engine’s coercion surface return SQLError::Unsupported.

cast_value_from

Cast a value while preserving an explicitly declared source type when the runtime carrier erases it. PostgreSQL 18 integer-to-bytea/oid casts and xid cast rejection require the source’s declared identity.

eval

Evaluate a value-producing expression. Function calls are not dispatched here; the compiler routes them through the function registry instead. Calling eval on a Func expr returns Unsupported so latent function-in-projection bugs surface loudly.

eval_binary_values

Apply a binary SQL operator to values that have already been evaluated. Execution engines use this when a hot path compiles expression traversal ahead of time but must retain the evaluator’s exact comparison, numeric promotion, NULL, overflow, and division-by-zero semantics.

eval_binary_values_with_integer_width

Evaluate an operator while retaining the integer type selected by SQL operator resolution. The dynamic Value carrier stores all integers as i64, so expression plans pass this width alongside the operands.

eval_comparison_truth

Compare two values without allocating an intermediate Value::Bool.

eval_function_call

Execute a scalar function after its argument expressions have already been evaluated.

evaluate_call_args

Evaluate a call’s argument list, unwrapping name => value markers into (Some(name), value) pairs.

integer_width_for_literal

integer_width_for_type

negate_value

Apply PostgreSQL prefix - while retaining the operand’s declared type.

parse_pg_array_literal

Parse a PostgreSQL array literal ({1,2,3}, {"a b",NULL}, {{1,2},{3,4}}) into nested lists of string/NULL values; the caller casts elements.

quote_ident

quote_ident: double-quote unless the identifier is a safe lower-case name that is not a keyword.

truthy

NULL is falsy; otherwise truthy iff the value coerces to a non-zero boolean / number / non-empty string.

unknown_function_error

function name(arg types) does not exist - the error PostgreSQL raises when call resolution fails (SQLSTATE 42883).

value_to_json_text

Render an engine value as PostgreSQL JSON input text without losing the lexical representation of values already typed as json or jsonb.

value_to_string

value_to_tensor

Coerce a Value into a tensor: an array of homogeneous numeric vectors. Used by TENSOR(N) columns to store chunk embeddings for one row while still indexing each vector element.

value_to_vector

Coerce a Value into a Vec<f32> if it is a homogeneous numeric list (used to read vector literals from ARRAY[...] or $N Vector params).

value_type_name

PostgreSQL-style type name used in function-resolution errors.