fix: restore iota blocks, asm --format flag and prose after the syntax pass

ast/ast.go

@@ -123,10 +123,8 @@ type Symbol struct {
 // OpKind classifies an operand syntactically.
 type OpKind int
 
-// Operand kinds.
 const (
-	OpInvalid   OpKind = iota
-	OpImmediate        // $value
+	OpImmediate = iota // $value
 	OpAddr             // register, memory reference, symbol or label
 )
 

ast/ast_test.go

@@ -54,11 +54,11 @@ func TestStmtPositions(t *testing.T) {
 // TestInterfaces confirms the node types satisfy their interfaces, so callers
 // can range over Decls and Stmts.
 func TestInterfaces(t *testing.T) {
-	var decls []Decl = []Decl{&Include{}, &Preproc{}, &Text{}, &Globl{}, &Data{}}
+	var decls = []Decl{&Include{}, &Preproc{}, &Text{}, &Globl{}, &Data{}}
 	if len(decls) != 5 {
 		t.Fatal("decl interface set")
 	}
-	var stmts []Stmt = []Stmt{&Label{}, &Instr{}}
+	var stmts = []Stmt{&Label{}, &Instr{}}
 	if len(stmts) != 2 {
 		t.Fatal("stmt interface set")
 	}