Expressions

Parsing, inspecting, substituting into, simplifying and evaluating expressions and equations.

Operation	Kind	Bindings	Summary
`closed_function_names`	function	Julia, TypeScript, Rust, Go	Return the v0.3.0 closed function set.
`contains`	function	TypeScript, Python, Rust, Go	Check if an expression contains a specific variable
`evaluate`	function	Python, Rust, Go	Evaluate a scalar AST expression against a dict of float variable bindings.
`evaluate_closed_function`	function	Julia, Rust, Go	Dispatch a closed function call.
`expand`	function	Python, Go	Public alias for `expand_document` using the spec’s spelling (esm-spec §9.6.4 rule 2).
`free_variables`	function	Julia, TypeScript, Python, Rust, Go	Extract all free (unbound) variable names from an expression.
`parse_equation`	function	Julia, TypeScript, Python, Rust, Go	Parse `lhs = rhs` into an `Equation`.
`parse_expression`	function	Julia, TypeScript, Python, Rust, Go	Parse a single expression string in the INFIX TEXT form into an AST expression — the inverse of `to_ascii`.
`simplify`	function	Julia, TypeScript, Python, Rust, Go	Perform constant folding and algebraic simplification on an expression.
`substitute`	function	Julia, TypeScript, Python, Rust, Go	Replace every variable named in `bindings` with its replacement expression, throughout `expr` (including faq bodies, filter predicates, integral bounds and every other…
`substitute_in_equations`	function	Julia, TypeScript, Go	Apply substitutions across all equations in a model.
`substitute_in_model`	function	TypeScript, Python, Rust, Go	Apply substitution across an ENTIRE model, not just its equations.
`substitute_in_model_with_context`	function	Rust, Go	`substitute_in_model` with scoped reference resolution.
`substitute_in_reaction_system`	function	TypeScript, Python, Rust, Go	Apply substitution across all rate expressions in a reaction system.
`substitute_in_reaction_system_with_context`	function	Rust, Go	`substitute_in_reaction_system` with scoped reference resolution.
`substitute_with_context`	function	Rust, Go	Substitute variables in an expression with scoped reference resolution (esm-spec §2.3.3).
`expr`	type	Python, Rust	An expression (esm-spec §4): a numeric literal (`int` or `float`), a variable or parameter reference (`str`), or an operator node (`ExprNode`) whose `args` are themselves…
`expr_node`	type	Python, Go	A node in an expression tree.
`closed_function_error`	error	Julia, TypeScript, Rust, Go	Raised by the closed function registry when the spec contract is violated.
`expression_parse_error`	error	Julia, TypeScript, Python, Rust, Go	Thrown when an expression string cannot be parsed by `parse_expression` or `parse_equation`.

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