return (node*)n;

}

/* Create pin pattern node (^var) */

static node*

new_pat_pin(parser_state *p, mrb_sym name)

{

struct mrb_ast_pat_pin_node *n = NEW_NODE(pat_pin, NODE_PAT_PIN);

n->name = name;

/* Pin operator references existing variable, does not create new binding */

return (node*)n;

}

/* Create as pattern node (pattern => var) */

static node*

new_pat_as(parser_state *p, node *pattern, mrb_sym name)

%type <id> f_label f_kwrest

/* pattern matching */

%type <nd> in_clauses p_expr p_alt p_value p_var p_as p_array p_array_body p_array_elems p_rest p_hash p_hash_body p_hash_elems p_hash_elem p_kwrest

%type <nd> in_clauses p_expr p_alt p_value p_var p_as p_array p_array_body p_array_elems p_rest p_hash p_hash_body p_hash_elems p_hash_elem p_kwrest p_args_head p_args_post

%token tUPLUS "unary plus"

%token tUMINUS "unary minus"

;

/* Pattern expressions for case/in */

/* Bracket-less array patterns: in 1, 2, x is same as in [1, 2, x] */

p_expr : p_as

| p_args_head p_as

{

$$ = new_pat_array(p, push($1, $2), 0, 0);

}

| p_args_head p_rest

{

$$ = new_pat_array(p, $1, $2, 0);

}

| p_args_head p_rest ',' p_args_post

{

$$ = new_pat_array(p, $1, $2, $4);

}

| p_rest

{

$$ = new_pat_array(p, 0, $1, 0);

}

| p_rest ',' p_args_post

{

$$ = new_pat_array(p, 0, $1, $3);

}

;

/* Comma-separated pattern list (prefix) */

p_args_head : p_as ','

{

$$ = list1($1);

}

| p_args_head p_as ','

{

$$ = push($1, $2);

}

;

/* Comma-separated pattern list (suffix, no trailing comma) */

p_args_post : p_as

{

$$ = list1($1);

}

| p_args_post ',' p_as

{

$$ = push($1, $3);

}

;

p_as : p_alt

}

| p_array

| p_hash

| '^' tIDENTIFIER

{

$$ = new_pat_pin(p, $2);

}

;

/* Array pattern: [a, b, *rest, c] */

}

;

/* Non-rest array pattern elements */

p_array_elems : p_expr

/* Non-rest array pattern elements - use p_as, not p_expr to avoid bracket-less recursion */

p_array_elems : p_as

{

$$ = list1($1);

}

| p_array_elems ',' p_expr

| p_array_elems ',' p_as

{

$$ = push($1, $3);

}