Crate panproto_expr 

panproto-expr

A pure functional expression language for panproto enriched theories.

This crate provides the computational substrate for schema transforms: coercion functions, merge/split logic, default value computation, and conflict resolution policies. Expressions are:

• Pure: no IO, no mutable state, no randomness
• Deterministic: same inputs always produce the same output
• Serializable: the Expr enum derives Serialize/Deserialize
• Platform-independent: evaluates identically on native and WASM
• Bounded: step and depth limits prevent runaway computation

The language is lambda calculus with pattern matching, records, lists, and ~50 built-in operations on strings, numbers, and collections.

Structs

Env

An evaluation environment mapping variable names to values.

EvalConfig

Configuration for the expression evaluator.

Enums

BuiltinOp

Built-in operations, grouped by domain.

Expr

An expression in the pure functional language.

ExprError

Errors that can occur during expression evaluation or type-checking.

Literal

A literal value in the expression language.

Pattern

A destructuring pattern for match expressions.

Functions

apply_builtin

Apply a builtin operation to evaluated arguments.

eval

Evaluate an expression in the given environment.

free_vars

Collect all free variables in an expression.

pattern_vars

Collect all variable names bound by a pattern.

substitute

Apply capture-avoiding substitution: replace name with replacement in expr.