Eval evaluates the given AST tree and returns its output value, the type of the output, and any error that occurred.

FixedValueTransform transforms an AST to return a fixed value for all interpolations.

Parse parses the given program and returns an executable AST tree.

EvalConfig is the configuration for evaluating.

IdentifierCheck is a SemanticCheck that checks that all identifiers resolve properly and that the right number of arguments are passed to functions.

TypeCheck implements ast.Visitor for type checking an AST tree.

EvalNode is the interface that must be implemented by any ast.Node to support evaluation.

TypeCheckNode is the interface that must be implemented by any ast.Node that wants to support type-checking.

SemanticChecker is the type that must be implemented to do a semantic check on an AST tree.