Declarations and statements

• var x T, var x T = e — explicit type; x := e — inferred from e (untyped constants default to int/float); nil cannot initialise :=.
• Package-level const only; package-level var is AES1105. State lives in script fields and components.
• Functions have fixed arity and zero or one result. A function that declares a result must end in a terminating statement (AES2013). Recursion is allowed up to depth 256.
• if, if … else if … else; for cond {}, for init; cond; post {}, for {}; break, continue.
• switch x { case a, b: … default: … } — no fallthrough; a switch on an enum must cover every member or have a default (AES2015); duplicate cases are errors.
• Compound assignment += -= *= /= %= and ++/-- on int/float lvalues; lvalues are variables, fields, lanes, slice elements, component fields and fields reached through a ScriptRef.
• A statement-level expression must be a call; an unused value is an error. Discarding the result of len, append, a conversion, Get<T>, GetScript<T> or Connect is an error. Discarding the result of start is allowed.
• Unused local variables are warnings.
• There are no closures, lambdas, defer, goroutines, pointers or maps.