# PEG grammar for Python

@trailer '''

void *

_PyPegen_parse(Parser *p)

{

// Initialize keywords

p->keywords = reserved_keywords;

p->n_keyword_lists = n_keyword_lists;

p->soft_keywords = soft_keywords;

// Run parser

void *result = NULL;

if (p->start_rule == Py_file_input) {

result = file_rule(p);

} else if (p->start_rule == Py_single_input) {

result = interactive_rule(p);

} else if (p->start_rule == Py_eval_input) {

result = eval_rule(p);

} else if (p->start_rule == Py_func_type_input) {

result = func_type_rule(p);

} else if (p->start_rule == Py_fstring_input) {

result = fstring_rule(p);

}

return result;

}

// The end

'''

file[mod_ty]: a=[statements] ENDMARKER { _PyPegen_make_module(p, a) }

interactive[mod_ty]: a=statement_newline { _PyAST_Interactive(a, p->arena) }

eval[mod_ty]: a=expressions NEWLINE* ENDMARKER { _PyAST_Expression(a, p->arena) }

func_type[mod_ty]: '(' a=[type_expressions] ')' '->' b=expression NEWLINE* ENDMARKER { _PyAST_FunctionType(a, b, p->arena) }

fstring[expr_ty]: star_expressions

# type_expressions allow */** but ignore them

type_expressions[asdl_expr_seq*]:

| a=','.expression+ ',' '*' b=expression ',' '**' c=expression {

(asdl_expr_seq*)_PyPegen_seq_append_to_end(

p,

CHECK(asdl_seq*, _PyPegen_seq_append_to_end(p, a, b)),

c) }

| a=','.expression+ ',' '*' b=expression { (asdl_expr_seq*)_PyPegen_seq_append_to_end(p, a, b) }

| a=','.expression+ ',' '**' b=expression { (asdl_expr_seq*)_PyPegen_seq_append_to_end(p, a, b) }

| '*' a=expression ',' '**' b=expression {

(asdl_expr_seq*)_PyPegen_seq_append_to_end(

p,

CHECK(asdl_seq*, _PyPegen_singleton_seq(p, a)),

b) }

| '*' a=expression { (asdl_expr_seq*)_PyPegen_singleton_seq(p, a) }

| '**' a=expression { (asdl_expr_seq*)_PyPegen_singleton_seq(p, a) }

| a[asdl_expr_seq*]=','.expression+ {a}

statements[asdl_stmt_seq*]: a=statement+ { (asdl_stmt_seq*)_PyPegen_seq_flatten(p, a) }

statement[asdl_stmt_seq*]: a=compound_stmt { (asdl_stmt_seq*)_PyPegen_singleton_seq(p, a) } | a[asdl_stmt_seq*]=simple_stmts { a }

statement_newline[asdl_stmt_seq*]:

| a=compound_stmt NEWLINE { (asdl_stmt_seq*)_PyPegen_singleton_seq(p, a) }

| simple_stmts

| NEWLINE { (asdl_stmt_seq*)_PyPegen_singleton_seq(p, CHECK(stmt_ty, _PyAST_Pass(EXTRA))) }

| ENDMARKER { _PyPegen_interactive_exit(p) }

simple_stmts[asdl_stmt_seq*]:

| a=simple_stmt !';' NEWLINE { (asdl_stmt_seq*)_PyPegen_singleton_seq(p, a) } # Not needed, there for speedup

| a[asdl_stmt_seq*]=';'.simple_stmt+ [';'] NEWLINE { a }

# NOTE: assignment MUST precede expression, else parsing a simple assignment

# will throw a SyntaxError.

simple_stmt[stmt_ty] (memo):

| assignment

| e=star_expressions { _PyAST_Expr(e, EXTRA) }

| &'return' return_stmt

| &('import' | 'from') import_stmt

| &'raise' raise_stmt

| 'pass' { _PyAST_Pass(EXTRA) }

| &'del' del_stmt

| &'yield' yield_stmt

| &'assert' assert_stmt

| 'break' { _PyAST_Break(EXTRA) }

| 'continue' { _PyAST_Continue(EXTRA) }

| &'global' global_stmt

| &'nonlocal' nonlocal_stmt

compound_stmt[stmt_ty]:

| &('def' | '@' | ASYNC) function_def

| &'if' if_stmt

| &('class' | '@') class_def

| &('with' | ASYNC) with_stmt

| &('for' | ASYNC) for_stmt

| &'try' try_stmt

| &'while' while_stmt

| match_stmt

# NOTE: annotated_rhs may start with 'yield'; yield_expr must start with 'yield'

assignment[stmt_ty]:

| a=NAME ':' b=expression c=['=' d=annotated_rhs { d }] {

CHECK_VERSION(

stmt_ty,

6,

"Variable annotation syntax is",

_PyAST_AnnAssign(CHECK(expr_ty, _PyPegen_set_expr_context(p, a, Store)), b, c, 1, EXTRA)

) }

| a=('(' b=single_target ')' { b }

| single_subscript_attribute_target) ':' b=expression c=['=' d=annotated_rhs { d }] {

CHECK_VERSION(stmt_ty, 6, "Variable annotations syntax is", _PyAST_AnnAssign(a, b, c, 0, EXTRA)) }

| a[asdl_expr_seq*]=(z=star_targets '=' { z })+ b=(yield_expr | star_expressions) !'=' tc=[TYPE_COMMENT] {

_PyAST_Assign(a, b, NEW_TYPE_COMMENT(p, tc), EXTRA) }

| a=single_target b=augassign ~ c=(yield_expr | star_expressions) {

_PyAST_AugAssign(a, b->kind, c, EXTRA) }

| invalid_assignment

augassign[AugOperator*]:

| '+=' { _PyPegen_augoperator(p, Add) }

| '-=' { _PyPegen_augoperator(p, Sub) }

| '*=' { _PyPegen_augoperator(p, Mult) }

| '@=' { CHECK_VERSION(AugOperator*, 5, "The '@' operator is", _PyPegen_augoperator(p, MatMult)) }

| '/=' { _PyPegen_augoperator(p, Div) }

| '%=' { _PyPegen_augoperator(p, Mod) }

| '&=' { _PyPegen_augoperator(p, BitAnd) }

| '|=' { _PyPegen_augoperator(p, BitOr) }

| '^=' { _PyPegen_augoperator(p, BitXor) }

| '<<=' { _PyPegen_augoperator(p, LShift) }

| '>>=' { _PyPegen_augoperator(p, RShift) }

| '**=' { _PyPegen_augoperator(p, Pow) }

| '//=' { _PyPegen_augoperator(p, FloorDiv) }

global_stmt[stmt_ty]: 'global' a[asdl_expr_seq*]=','.NAME+ {

_PyAST_Global(CHECK(asdl_identifier_seq*, _PyPegen_map_names_to_ids(p, a)), EXTRA) }

nonlocal_stmt[stmt_ty]: 'nonlocal' a[asdl_expr_seq*]=','.NAME+ {

_PyAST_Nonlocal(CHECK(asdl_identifier_seq*, _PyPegen_map_names_to_ids(p, a)), EXTRA) }

yield_stmt[stmt_ty]: y=yield_expr { _PyAST_Expr(y, EXTRA) }

assert_stmt[stmt_ty]: 'assert' a=expression b=[',' z=expression { z }] { _PyAST_Assert(a, b, EXTRA) }

del_stmt[stmt_ty]:

| 'del' a=del_targets &(';' | NEWLINE) { _PyAST_Delete(a, EXTRA) }

| invalid_del_stmt

import_stmt[stmt_ty]: import_name | import_from

import_name[stmt_ty]: 'import' a=dotted_as_names { _PyAST_Import(a, EXTRA) }

# note below: the ('.' | '...') is necessary because '...' is tokenized as ELLIPSIS

import_from[stmt_ty]:

| 'from' a=('.' | '...')* b=dotted_name 'import' c=import_from_targets {

_PyAST_ImportFrom(b->v.Name.id, c, _PyPegen_seq_count_dots(a), EXTRA) }

| 'from' a=('.' | '...')+ 'import' b=import_from_targets {

_PyAST_ImportFrom(NULL, b, _PyPegen_seq_count_dots(a), EXTRA) }

import_from_targets[asdl_alias_seq*]:

| '(' a=import_from_as_names [','] ')' { a }

| import_from_as_names !','

| '*' { (asdl_alias_seq*)_PyPegen_singleton_seq(p, CHECK(alias_ty, _PyPegen_alias_for_star(p, EXTRA))) }

| invalid_import_from_targets

import_from_as_names[asdl_alias_seq*]:

| a[asdl_alias_seq*]=','.import_from_as_name+ { a }

import_from_as_name[alias_ty]:

| a=NAME b=['as' z=NAME { z }] { _PyAST_alias(a->v.Name.id,

(b) ? ((expr_ty) b)->v.Name.id : NULL,

EXTRA) }

dotted_as_names[asdl_alias_seq*]:

| a[asdl_alias_seq*]=','.dotted_as_name+ { a }

dotted_as_name[alias_ty]:

| a=dotted_name b=['as' z=NAME { z }] { _PyAST_alias(a->v.Name.id,

(b) ? ((expr_ty) b)->v.Name.id : NULL,

EXTRA) }

dotted_name[expr_ty]:

| a=dotted_name '.' b=NAME { _PyPegen_join_names_with_dot(p, a, b) }

| NAME

if_stmt[stmt_ty]:

| invalid_if_stmt

| 'if' a=named_expression ':' b=block c=elif_stmt {

_PyAST_If(a, b, CHECK(asdl_stmt_seq*, _PyPegen_singleton_seq(p, c)), EXTRA) }

| 'if' a=named_expression ':' b=block c=[else_block] { _PyAST_If(a, b, c, EXTRA) }

elif_stmt[stmt_ty]:

| invalid_elif_stmt

| 'elif' a=named_expression ':' b=block c=elif_stmt {

_PyAST_If(a, b, CHECK(asdl_stmt_seq*, _PyPegen_singleton_seq(p, c)), EXTRA) }

| 'elif' a=named_expression ':' b=block c=[else_block] { _PyAST_If(a, b, c, EXTRA) }

else_block[asdl_stmt_seq*]:

| invalid_else_stmt

| 'else' &&':' b=block { b }

while_stmt[stmt_ty]:

| invalid_while_stmt

| 'while' a=named_expression ':' b=block c=[else_block] { _PyAST_While(a, b, c, EXTRA) }

for_stmt[stmt_ty]:

| invalid_for_stmt

| 'for' t=star_targets 'in' ~ ex=star_expressions ':' tc=[TYPE_COMMENT] b=block el=[else_block] {

_PyAST_For(t, ex, b, el, NEW_TYPE_COMMENT(p, tc), EXTRA) }

| ASYNC 'for' t=star_targets 'in' ~ ex=star_expressions ':' tc=[TYPE_COMMENT] b=block el=[else_block] {

CHECK_VERSION(stmt_ty, 5, "Async for loops are", _PyAST_AsyncFor(t, ex, b, el, NEW_TYPE_COMMENT(p, tc), EXTRA)) }

| invalid_for_target

with_stmt[stmt_ty]:

| invalid_with_stmt_indent

| 'with' '(' a[asdl_withitem_seq*]=','.with_item+ ','? ')' ':' b=block {

CHECK_VERSION(stmt_ty, 9, "Parenthesized context managers are", _PyAST_With(a, b, NULL, EXTRA)) }

| 'with' a[asdl_withitem_seq*]=','.with_item+ ':' tc=[TYPE_COMMENT] b=block {

_PyAST_With(a, b, NEW_TYPE_COMMENT(p, tc), EXTRA) }

| ASYNC 'with' '(' a[asdl_withitem_seq*]=','.with_item+ ','? ')' ':' b=block {

CHECK_VERSION(stmt_ty, 5, "Async with statements are", _PyAST_AsyncWith(a, b, NULL, EXTRA)) }

| ASYNC 'with' a[asdl_withitem_seq*]=','.with_item+ ':' tc=[TYPE_COMMENT] b=block {

CHECK_VERSION(stmt_ty, 5, "Async with statements are", _PyAST_AsyncWith(a, b, NEW_TYPE_COMMENT(p, tc), EXTRA)) }

| invalid_with_stmt

with_item[withitem_ty]:

| e=expression 'as' t=star_target &(',' | ')' | ':') { _PyAST_withitem(e, t, p->arena) }

| invalid_with_item

| e=expression { _PyAST_withitem(e, NULL, p->arena) }

try_stmt[stmt_ty]:

| invalid_try_stmt

| 'try' &&':' b=block f=finally_block { _PyAST_Try(b, NULL, NULL, f, EXTRA) }

| 'try' &&':' b=block ex[asdl_excepthandler_seq*]=except_block+ el=[else_block] f=[finally_block] { _PyAST_Try(b, ex, el, f, EXTRA) }

except_block[excepthandler_ty]:

| invalid_except_stmt_indent

| 'except' e=expression t=['as' z=NAME { z }] ':' b=block {

_PyAST_ExceptHandler(e, (t) ? ((expr_ty) t)->v.Name.id : NULL, b, EXTRA) }

| 'except' ':' b=block { _PyAST_ExceptHandler(NULL, NULL, b, EXTRA) }

| invalid_except_stmt

finally_block[asdl_stmt_seq*]:

| invalid_finally_stmt

| 'finally' &&':' a=block { a }

match_stmt[stmt_ty]:

| "match" subject=subject_expr ':' NEWLINE INDENT cases[asdl_match_case_seq*]=case_block+ DEDENT {

CHECK_VERSION(stmt_ty, 10, "Pattern matching is", _PyAST_Match(subject, cases, EXTRA)) }

| invalid_match_stmt

subject_expr[expr_ty]:

| value=star_named_expression ',' values=star_named_expressions? {

_PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, value, values)), Load, EXTRA) }

| named_expression

case_block[match_case_ty]:

| invalid_case_block

| "case" pattern=patterns guard=guard? ':' body=block {

_PyAST_match_case(pattern, guard, body, p->arena) }

guard[expr_ty]: 'if' guard=named_expression { guard }

patterns[pattern_ty]:

| patterns[asdl_pattern_seq*]=open_sequence_pattern {

_PyAST_MatchSequence(patterns, EXTRA) }

| pattern

pattern[pattern_ty]:

| as_pattern

| or_pattern

as_pattern[pattern_ty]:

| pattern=or_pattern 'as' target=pattern_capture_target {

_PyAST_MatchAs(pattern, target->v.Name.id, EXTRA) }

| invalid_as_pattern

or_pattern[pattern_ty]:

| patterns[asdl_pattern_seq*]='|'.closed_pattern+ {

asdl_seq_LEN(patterns) == 1 ? asdl_seq_GET(patterns, 0) : _PyAST_MatchOr(patterns, EXTRA) }

closed_pattern[pattern_ty] (memo):

| literal_pattern

| capture_pattern

| wildcard_pattern

| value_pattern

| group_pattern

| sequence_pattern

| mapping_pattern

| class_pattern

# Literal patterns are used for equality and identity constraints

literal_pattern[pattern_ty]:

| value=signed_number !('+' | '-') { _PyAST_MatchValue(value, EXTRA) }

| value=complex_number { _PyAST_MatchValue(value, EXTRA) }

| value=strings { _PyAST_MatchValue(value, EXTRA) }

| 'None' { _PyAST_MatchSingleton(Py_None, EXTRA) }

| 'True' { _PyAST_MatchSingleton(Py_True, EXTRA) }

| 'False' { _PyAST_MatchSingleton(Py_False, EXTRA) }

# Literal expressions are used to restrict permitted mapping pattern keys

literal_expr[expr_ty]:

| signed_number !('+' | '-')

| complex_number

| strings

| 'None' { _PyAST_Constant(Py_None, NULL, EXTRA) }

| 'True' { _PyAST_Constant(Py_True, NULL, EXTRA) }

| 'False' { _PyAST_Constant(Py_False, NULL, EXTRA) }

complex_number[expr_ty]:

| real=signed_real_number '+' imag=imaginary_number {

_PyAST_BinOp(real, Add, imag, EXTRA) }

| real=signed_real_number '-' imag=imaginary_number {

_PyAST_BinOp(real, Sub, imag, EXTRA) }

signed_number[expr_ty]:

| NUMBER

| '-' number=NUMBER { _PyAST_UnaryOp(USub, number, EXTRA) }

signed_real_number[expr_ty]:

| real_number

| '-' real=real_number { _PyAST_UnaryOp(USub, real, EXTRA) }

real_number[expr_ty]:

| real=NUMBER { _PyPegen_ensure_real(p, real) }

imaginary_number[expr_ty]:

| imag=NUMBER { _PyPegen_ensure_imaginary(p, imag) }

capture_pattern[pattern_ty]:

| target=pattern_capture_target { _PyAST_MatchAs(NULL, target->v.Name.id, EXTRA) }

pattern_capture_target[expr_ty]:

| !"_" name=NAME !('.' | '(' | '=') {

_PyPegen_set_expr_context(p, name, Store) }

wildcard_pattern[pattern_ty]:

| "_" { _PyAST_MatchAs(NULL, NULL, EXTRA) }

value_pattern[pattern_ty]:

| attr=attr !('.' | '(' | '=') { _PyAST_MatchValue(attr, EXTRA) }

attr[expr_ty]:

| value=name_or_attr '.' attr=NAME {

_PyAST_Attribute(value, attr->v.Name.id, Load, EXTRA) }

name_or_attr[expr_ty]:

| attr

| NAME

group_pattern[pattern_ty]:

| '(' pattern=pattern ')' { pattern }

sequence_pattern[pattern_ty]:

| '[' patterns=maybe_sequence_pattern? ']' { _PyAST_MatchSequence(patterns, EXTRA) }

| '(' patterns=open_sequence_pattern? ')' { _PyAST_MatchSequence(patterns, EXTRA) }

open_sequence_pattern[asdl_seq*]:

| pattern=maybe_star_pattern ',' patterns=maybe_sequence_pattern? {

_PyPegen_seq_insert_in_front(p, pattern, patterns) }

maybe_sequence_pattern[asdl_seq*]:

| patterns=','.maybe_star_pattern+ ','? { patterns }

maybe_star_pattern[pattern_ty]:

| star_pattern

| pattern

star_pattern[pattern_ty] (memo):

| '*' target=pattern_capture_target {

_PyAST_MatchStar(target->v.Name.id, EXTRA) }

| '*' wildcard_pattern {

_PyAST_MatchStar(NULL, EXTRA) }

mapping_pattern[pattern_ty]:

| '{' '}' {

_PyAST_MatchMapping(NULL, NULL, NULL, EXTRA) }

| '{' rest=double_star_pattern ','? '}' {

_PyAST_MatchMapping(NULL, NULL, rest->v.Name.id, EXTRA) }

| '{' items=items_pattern ',' rest=double_star_pattern ','? '}' {

_PyAST_MatchMapping(

CHECK(asdl_expr_seq*, _PyPegen_get_pattern_keys(p, items)),

CHECK(asdl_pattern_seq*, _PyPegen_get_patterns(p, items)),

rest->v.Name.id,

EXTRA) }

| '{' items=items_pattern ','? '}' {

_PyAST_MatchMapping(

CHECK(asdl_expr_seq*, _PyPegen_get_pattern_keys(p, items)),

CHECK(asdl_pattern_seq*, _PyPegen_get_patterns(p, items)),

NULL,

EXTRA) }

items_pattern[asdl_seq*]:

| ','.key_value_pattern+

key_value_pattern[KeyPatternPair*]:

| key=(literal_expr | attr) ':' pattern=pattern {

_PyPegen_key_pattern_pair(p, key, pattern) }

double_star_pattern[expr_ty]:

| '**' target=pattern_capture_target { target }

class_pattern[pattern_ty]:

| cls=name_or_attr '(' ')' {

_PyAST_MatchClass(cls, NULL, NULL, NULL, EXTRA) }

| cls=name_or_attr '(' patterns=positional_patterns ','? ')' {

_PyAST_MatchClass(cls, patterns, NULL, NULL, EXTRA) }

| cls=name_or_attr '(' keywords=keyword_patterns ','? ')' {

_PyAST_MatchClass(

cls, NULL,

CHECK(asdl_identifier_seq*, _PyPegen_map_names_to_ids(p,

CHECK(asdl_expr_seq*, _PyPegen_get_pattern_keys(p, keywords)))),

CHECK(asdl_pattern_seq*, _PyPegen_get_patterns(p, keywords)),

EXTRA) }

| cls=name_or_attr '(' patterns=positional_patterns ',' keywords=keyword_patterns ','? ')' {

_PyAST_MatchClass(

cls,

patterns,

CHECK(asdl_identifier_seq*, _PyPegen_map_names_to_ids(p,

CHECK(asdl_expr_seq*, _PyPegen_get_pattern_keys(p, keywords)))),

CHECK(asdl_pattern_seq*, _PyPegen_get_patterns(p, keywords)),

EXTRA) }

| invalid_class_pattern

positional_patterns[asdl_pattern_seq*]:

| args[asdl_pattern_seq*]=','.pattern+ { args }

keyword_patterns[asdl_seq*]:

| ','.keyword_pattern+

keyword_pattern[KeyPatternPair*]:

| arg=NAME '=' value=pattern { _PyPegen_key_pattern_pair(p, arg, value) }

return_stmt[stmt_ty]:

| 'return' a=[star_expressions] { _PyAST_Return(a, EXTRA) }

raise_stmt[stmt_ty]:

| 'raise' a=expression b=['from' z=expression { z }] { _PyAST_Raise(a, b, EXTRA) }

| 'raise' { _PyAST_Raise(NULL, NULL, EXTRA) }

function_def[stmt_ty]:

| d=decorators f=function_def_raw { _PyPegen_function_def_decorators(p, d, f) }

| function_def_raw

function_def_raw[stmt_ty]:

| invalid_def_raw

| 'def' n=NAME '(' params=[params] ')' a=['->' z=expression { z }] &&':' tc=[func_type_comment] b=block {

_PyAST_FunctionDef(n->v.Name.id,

(params) ? params : CHECK(arguments_ty, _PyPegen_empty_arguments(p)),

b, NULL, a, NEW_TYPE_COMMENT(p, tc), EXTRA) }

| ASYNC 'def' n=NAME '(' params=[params] ')' a=['->' z=expression { z }] &&':' tc=[func_type_comment] b=block {

CHECK_VERSION(

stmt_ty,

5,

"Async functions are",

_PyAST_AsyncFunctionDef(n->v.Name.id,

(params) ? params : CHECK(arguments_ty, _PyPegen_empty_arguments(p)),

b, NULL, a, NEW_TYPE_COMMENT(p, tc), EXTRA)

) }

func_type_comment[Token*]:

| NEWLINE t=TYPE_COMMENT &(NEWLINE INDENT) { t } # Must be followed by indented block

| invalid_double_type_comments

| TYPE_COMMENT

params[arguments_ty]:

| invalid_parameters

| parameters

parameters[arguments_ty]:

| a=slash_no_default b[asdl_arg_seq*]=param_no_default* c=param_with_default* d=[star_etc] {

CHECK_VERSION(arguments_ty, 8, "Positional-only parameters are", _PyPegen_make_arguments(p, a, NULL, b, c, d)) }

| a=slash_with_default b=param_with_default* c=[star_etc] {

CHECK_VERSION(arguments_ty, 8, "Positional-only parameters are", _PyPegen_make_arguments(p, NULL, a, NULL, b, c)) }

| a[asdl_arg_seq*]=param_no_default+ b=param_with_default* c=[star_etc] {

_PyPegen_make_arguments(p, NULL, NULL, a, b, c) }

| a=param_with_default+ b=[star_etc] { _PyPegen_make_arguments(p, NULL, NULL, NULL, a, b)}

| a=star_etc { _PyPegen_make_arguments(p, NULL, NULL, NULL, NULL, a) }

# Some duplication here because we can't write (',' | &')'),

# which is because we don't support empty alternatives (yet).

#

slash_no_default[asdl_arg_seq*]:

| a[asdl_arg_seq*]=param_no_default+ '/' ',' { a }

| a[asdl_arg_seq*]=param_no_default+ '/' &')' { a }

slash_with_default[SlashWithDefault*]:

| a=param_no_default* b=param_with_default+ '/' ',' { _PyPegen_slash_with_default(p, (asdl_arg_seq *)a, b) }

| a=param_no_default* b=param_with_default+ '/' &')' { _PyPegen_slash_with_default(p, (asdl_arg_seq *)a, b) }

star_etc[StarEtc*]:

| '*' a=param_no_default b=param_maybe_default* c=[kwds] {

_PyPegen_star_etc(p, a, b, c) }

| '*' ',' b=param_maybe_default+ c=[kwds] {

_PyPegen_star_etc(p, NULL, b, c) }

| a=kwds { _PyPegen_star_etc(p, NULL, NULL, a) }

| invalid_star_etc

kwds[arg_ty]: '**' a=param_no_default { a }

# One parameter. This *includes* a following comma and type comment.

#

# There are three styles:

# - No default

# - With default

# - Maybe with default

#

# There are two alternative forms of each, to deal with type comments:

# - Ends in a comma followed by an optional type comment

# - No comma, optional type comment, must be followed by close paren

# The latter form is for a final parameter without trailing comma.

#

param_no_default[arg_ty]:

| a=param ',' tc=TYPE_COMMENT? { _PyPegen_add_type_comment_to_arg(p, a, tc) }

| a=param tc=TYPE_COMMENT? &')' { _PyPegen_add_type_comment_to_arg(p, a, tc) }

param_with_default[NameDefaultPair*]:

| a=param c=default ',' tc=TYPE_COMMENT? { _PyPegen_name_default_pair(p, a, c, tc) }

| a=param c=default tc=TYPE_COMMENT? &')' { _PyPegen_name_default_pair(p, a, c, tc) }

param_maybe_default[NameDefaultPair*]:

| a=param c=default? ',' tc=TYPE_COMMENT? { _PyPegen_name_default_pair(p, a, c, tc) }

| a=param c=default? tc=TYPE_COMMENT? &')' { _PyPegen_name_default_pair(p, a, c, tc) }

param[arg_ty]: a=NAME b=annotation? { _PyAST_arg(a->v.Name.id, b, NULL, EXTRA) }

annotation[expr_ty]: ':' a=expression { a }

default[expr_ty]: '=' a=expression { a }

decorators[asdl_expr_seq*]: a[asdl_expr_seq*]=('@' f=named_expression NEWLINE { f })+ { a }

class_def[stmt_ty]:

| a=decorators b=class_def_raw { _PyPegen_class_def_decorators(p, a, b) }

| class_def_raw

class_def_raw[stmt_ty]:

| invalid_class_def_raw

| 'class' a=NAME b=['(' z=[arguments] ')' { z }] ':' c=block {

_PyAST_ClassDef(a->v.Name.id,

(b) ? ((expr_ty) b)->v.Call.args : NULL,

(b) ? ((expr_ty) b)->v.Call.keywords : NULL,

c, NULL, EXTRA) }

block[asdl_stmt_seq*] (memo):

| NEWLINE INDENT a=statements DEDENT { a }

| simple_stmts

| invalid_block

star_expressions[expr_ty]:

| a=star_expression b=(',' c=star_expression { c })+ [','] {

_PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)), Load, EXTRA) }

| a=star_expression ',' { _PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_singleton_seq(p, a)), Load, EXTRA) }

| star_expression

star_expression[expr_ty] (memo):

| '*' a=bitwise_or { _PyAST_Starred(a, Load, EXTRA) }

| expression

star_named_expressions[asdl_expr_seq*]: a[asdl_expr_seq*]=','.star_named_expression+ [','] { a }

star_named_expression[expr_ty]:

| '*' a=bitwise_or { _PyAST_Starred(a, Load, EXTRA) }

| named_expression

assignment_expression[expr_ty]:

| a=NAME ':=' ~ b=expression {

CHECK_VERSION(expr_ty, 8, "Assignment expressions are",

_PyAST_NamedExpr(CHECK(expr_ty, _PyPegen_set_expr_context(p, a, Store)), b, EXTRA)) }

named_expression[expr_ty]:

| assignment_expression

| invalid_named_expression

| expression !':='

annotated_rhs[expr_ty]: yield_expr | star_expressions

expressions[expr_ty]:

| a=expression b=(',' c=expression { c })+ [','] {

_PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)), Load, EXTRA) }

| a=expression ',' { _PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_singleton_seq(p, a)), Load, EXTRA) }

| expression

expression[expr_ty] (memo):

| invalid_expression

| invalid_legacy_expression

| a=disjunction 'if' b=disjunction 'else' c=expression { _PyAST_IfExp(b, a, c, EXTRA) }

| disjunction

| lambdef

lambdef[expr_ty]:

| 'lambda' a=[lambda_params] ':' b=expression {

_PyAST_Lambda((a) ? a : CHECK(arguments_ty, _PyPegen_empty_arguments(p)), b, EXTRA) }

lambda_params[arguments_ty]:

| invalid_lambda_parameters

| lambda_parameters

# lambda_parameters etc. duplicates parameters but without annotations

# or type comments, and if there's no comma after a parameter, we expect

# a colon, not a close parenthesis. (For more, see parameters above.)

#

lambda_parameters[arguments_ty]:

| a=lambda_slash_no_default b[asdl_arg_seq*]=lambda_param_no_default* c=lambda_param_with_default* d=[lambda_star_etc] {

CHECK_VERSION(arguments_ty, 8, "Positional-only parameters are", _PyPegen_make_arguments(p, a, NULL, b, c, d)) }

| a=lambda_slash_with_default b=lambda_param_with_default* c=[lambda_star_etc] {

CHECK_VERSION(arguments_ty, 8, "Positional-only parameters are", _PyPegen_make_arguments(p, NULL, a, NULL, b, c)) }

| a[asdl_arg_seq*]=lambda_param_no_default+ b=lambda_param_with_default* c=[lambda_star_etc] {

_PyPegen_make_arguments(p, NULL, NULL, a, b, c) }

| a=lambda_param_with_default+ b=[lambda_star_etc] { _PyPegen_make_arguments(p, NULL, NULL, NULL, a, b)}

| a=lambda_star_etc { _PyPegen_make_arguments(p, NULL, NULL, NULL, NULL, a) }

lambda_slash_no_default[asdl_arg_seq*]:

| a[asdl_arg_seq*]=lambda_param_no_default+ '/' ',' { a }

| a[asdl_arg_seq*]=lambda_param_no_default+ '/' &':' { a }

lambda_slash_with_default[SlashWithDefault*]:

| a=lambda_param_no_default* b=lambda_param_with_default+ '/' ',' { _PyPegen_slash_with_default(p, (asdl_arg_seq *)a, b) }

| a=lambda_param_no_default* b=lambda_param_with_default+ '/' &':' { _PyPegen_slash_with_default(p, (asdl_arg_seq *)a, b) }

lambda_star_etc[StarEtc*]:

| '*' a=lambda_param_no_default b=lambda_param_maybe_default* c=[lambda_kwds] {

_PyPegen_star_etc(p, a, b, c) }

| '*' ',' b=lambda_param_maybe_default+ c=[lambda_kwds] {

_PyPegen_star_etc(p, NULL, b, c) }

| a=lambda_kwds { _PyPegen_star_etc(p, NULL, NULL, a) }

| invalid_lambda_star_etc

lambda_kwds[arg_ty]: '**' a=lambda_param_no_default { a }

lambda_param_no_default[arg_ty]:

| a=lambda_param ',' { a }

| a=lambda_param &':' { a }

lambda_param_with_default[NameDefaultPair*]:

| a=lambda_param c=default ',' { _PyPegen_name_default_pair(p, a, c, NULL) }

| a=lambda_param c=default &':' { _PyPegen_name_default_pair(p, a, c, NULL) }

lambda_param_maybe_default[NameDefaultPair*]:

| a=lambda_param c=default? ',' { _PyPegen_name_default_pair(p, a, c, NULL) }

| a=lambda_param c=default? &':' { _PyPegen_name_default_pair(p, a, c, NULL) }

lambda_param[arg_ty]: a=NAME { _PyAST_arg(a->v.Name.id, NULL, NULL, EXTRA) }

disjunction[expr_ty] (memo):

| a=conjunction b=('or' c=conjunction { c })+ { _PyAST_BoolOp(

Or,

CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)),

EXTRA) }

| conjunction

conjunction[expr_ty] (memo):

| a=inversion b=('and' c=inversion { c })+ { _PyAST_BoolOp(

And,

CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)),

EXTRA) }

| inversion

inversion[expr_ty] (memo):

| 'not' a=inversion { _PyAST_UnaryOp(Not, a, EXTRA) }

| comparison

comparison[expr_ty]:

| a=bitwise_or b=compare_op_bitwise_or_pair+ {

_PyAST_Compare(

a,

CHECK(asdl_int_seq*, _PyPegen_get_cmpops(p, b)),

CHECK(asdl_expr_seq*, _PyPegen_get_exprs(p, b)),

EXTRA) }

| bitwise_or

compare_op_bitwise_or_pair[CmpopExprPair*]:

| eq_bitwise_or

| noteq_bitwise_or

| lte_bitwise_or

| lt_bitwise_or

| gte_bitwise_or

| gt_bitwise_or

| notin_bitwise_or

| in_bitwise_or

| isnot_bitwise_or

| is_bitwise_or

eq_bitwise_or[CmpopExprPair*]: '==' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, Eq, a) }

noteq_bitwise_or[CmpopExprPair*]:

| (tok='!=' { _PyPegen_check_barry_as_flufl(p, tok) ? NULL : tok}) a=bitwise_or {_PyPegen_cmpop_expr_pair(p, NotEq, a) }

lte_bitwise_or[CmpopExprPair*]: '<=' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, LtE, a) }

lt_bitwise_or[CmpopExprPair*]: '<' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, Lt, a) }

gte_bitwise_or[CmpopExprPair*]: '>=' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, GtE, a) }

gt_bitwise_or[CmpopExprPair*]: '>' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, Gt, a) }

notin_bitwise_or[CmpopExprPair*]: 'not' 'in' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, NotIn, a) }

in_bitwise_or[CmpopExprPair*]: 'in' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, In, a) }

isnot_bitwise_or[CmpopExprPair*]: 'is' 'not' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, IsNot, a) }

is_bitwise_or[CmpopExprPair*]: 'is' a=bitwise_or { _PyPegen_cmpop_expr_pair(p, Is, a) }

bitwise_or[expr_ty]:

| a=bitwise_or '|' b=bitwise_xor { _PyAST_BinOp(a, BitOr, b, EXTRA) }

| bitwise_xor

bitwise_xor[expr_ty]:

| a=bitwise_xor '^' b=bitwise_and { _PyAST_BinOp(a, BitXor, b, EXTRA) }

| bitwise_and

bitwise_and[expr_ty]:

| a=bitwise_and '&' b=shift_expr { _PyAST_BinOp(a, BitAnd, b, EXTRA) }

| shift_expr

shift_expr[expr_ty]:

| a=shift_expr '<<' b=sum { _PyAST_BinOp(a, LShift, b, EXTRA) }

| a=shift_expr '>>' b=sum { _PyAST_BinOp(a, RShift, b, EXTRA) }

| sum

sum[expr_ty]:

| a=sum '+' b=term { _PyAST_BinOp(a, Add, b, EXTRA) }

| a=sum '-' b=term { _PyAST_BinOp(a, Sub, b, EXTRA) }

| term

term[expr_ty]:

| a=term '*' b=factor { _PyAST_BinOp(a, Mult, b, EXTRA) }

| a=term '/' b=factor { _PyAST_BinOp(a, Div, b, EXTRA) }

| a=term '//' b=factor { _PyAST_BinOp(a, FloorDiv, b, EXTRA) }

| a=term '%' b=factor { _PyAST_BinOp(a, Mod, b, EXTRA) }

| a=term '@' b=factor { CHECK_VERSION(expr_ty, 5, "The '@' operator is", _PyAST_BinOp(a, MatMult, b, EXTRA)) }

| factor

factor[expr_ty] (memo):

| '+' a=factor { _PyAST_UnaryOp(UAdd, a, EXTRA) }

| '-' a=factor { _PyAST_UnaryOp(USub, a, EXTRA) }

| '~' a=factor { _PyAST_UnaryOp(Invert, a, EXTRA) }

| power

power[expr_ty]:

| a=await_primary '**' b=factor { _PyAST_BinOp(a, Pow, b, EXTRA) }

| await_primary

await_primary[expr_ty] (memo):

| AWAIT a=primary { CHECK_VERSION(expr_ty, 5, "Await expressions are", _PyAST_Await(a, EXTRA)) }

| primary

primary[expr_ty]:

| a=primary '.' b=NAME { _PyAST_Attribute(a, b->v.Name.id, Load, EXTRA) }

| a=primary b=genexp { _PyAST_Call(a, CHECK(asdl_expr_seq*, (asdl_expr_seq*)_PyPegen_singleton_seq(p, b)), NULL, EXTRA) }

| a=primary '(' b=[arguments] ')' {

_PyAST_Call(a,

(b) ? ((expr_ty) b)->v.Call.args : NULL,

(b) ? ((expr_ty) b)->v.Call.keywords : NULL,

EXTRA) }

| a=primary '[' b=slices ']' { _PyAST_Subscript(a, b, Load, EXTRA) }

| atom

slices[expr_ty]:

| a=slice !',' { a }

| a[asdl_expr_seq*]=','.slice+ [','] { _PyAST_Tuple(a, Load, EXTRA) }

slice[expr_ty]:

| a=[expression] ':' b=[expression] c=[':' d=[expression] { d }] { _PyAST_Slice(a, b, c, EXTRA) }

| a=named_expression { a }

atom[expr_ty]:

| NAME

| 'True' { _PyAST_Constant(Py_True, NULL, EXTRA) }

| 'False' { _PyAST_Constant(Py_False, NULL, EXTRA) }

| 'None' { _PyAST_Constant(Py_None, NULL, EXTRA) }

| &STRING strings

| NUMBER

| &'(' (tuple | group | genexp)

| &'[' (list | listcomp)

| &'{' (dict | set | dictcomp | setcomp)

| '...' { _PyAST_Constant(Py_Ellipsis, NULL, EXTRA) }

strings[expr_ty] (memo): a=STRING+ { _PyPegen_concatenate_strings(p, a) }

list[expr_ty]:

| '[' a=[star_named_expressions] ']' { _PyAST_List(a, Load, EXTRA) }

listcomp[expr_ty]:

| '[' a=named_expression b=for_if_clauses ']' { _PyAST_ListComp(a, b, EXTRA) }

| invalid_comprehension

tuple[expr_ty]:

| '(' a=[y=star_named_expression ',' z=[star_named_expressions] { _PyPegen_seq_insert_in_front(p, y, z) } ] ')' {

_PyAST_Tuple(a, Load, EXTRA) }

group[expr_ty]:

| '(' a=(yield_expr | named_expression) ')' { a }

| invalid_group

genexp[expr_ty]:

| '(' a=( assignment_expression | expression !':=') b=for_if_clauses ')' { _PyAST_GeneratorExp(a, b, EXTRA) }

| invalid_comprehension

set[expr_ty]: '{' a=star_named_expressions '}' { _PyAST_Set(a, EXTRA) }

setcomp[expr_ty]:

| '{' a=named_expression b=for_if_clauses '}' { _PyAST_SetComp(a, b, EXTRA) }

| invalid_comprehension

dict[expr_ty]:

| '{' a=[double_starred_kvpairs] '}' {

_PyAST_Dict(

CHECK(asdl_expr_seq*, _PyPegen_get_keys(p, a)),

CHECK(asdl_expr_seq*, _PyPegen_get_values(p, a)),

EXTRA) }

| '{' invalid_double_starred_kvpairs '}'

dictcomp[expr_ty]:

| '{' a=kvpair b=for_if_clauses '}' { _PyAST_DictComp(a->key, a->value, b, EXTRA) }

| invalid_dict_comprehension

double_starred_kvpairs[asdl_seq*]: a=','.double_starred_kvpair+ [','] { a }

double_starred_kvpair[KeyValuePair*]:

| '**' a=bitwise_or { _PyPegen_key_value_pair(p, NULL, a) }

| kvpair

kvpair[KeyValuePair*]: a=expression ':' b=expression { _PyPegen_key_value_pair(p, a, b) }

for_if_clauses[asdl_comprehension_seq*]:

| a[asdl_comprehension_seq*]=for_if_clause+ { a }

for_if_clause[comprehension_ty]:

| ASYNC 'for' a=star_targets 'in' ~ b=disjunction c[asdl_expr_seq*]=('if' z=disjunction { z })* {

CHECK_VERSION(comprehension_ty, 6, "Async comprehensions are", _PyAST_comprehension(a, b, c, 1, p->arena)) }

| 'for' a=star_targets 'in' ~ b=disjunction c[asdl_expr_seq*]=('if' z=disjunction { z })* {

_PyAST_comprehension(a, b, c, 0, p->arena) }

| invalid_for_target

yield_expr[expr_ty]:

| 'yield' 'from' a=expression { _PyAST_YieldFrom(a, EXTRA) }

| 'yield' a=[star_expressions] { _PyAST_Yield(a, EXTRA) }

arguments[expr_ty] (memo):

| a=args [','] &')' { a }

| invalid_arguments

args[expr_ty]:

| a[asdl_expr_seq*]=','.(starred_expression | ( assignment_expression | expression !':=') !'=')+ b=[',' k=kwargs {k}] {

_PyPegen_collect_call_seqs(p, a, b, EXTRA) }

| a=kwargs { _PyAST_Call(_PyPegen_dummy_name(p),

CHECK_NULL_ALLOWED(asdl_expr_seq*, _PyPegen_seq_extract_starred_exprs(p, a)),

CHECK_NULL_ALLOWED(asdl_keyword_seq*, _PyPegen_seq_delete_starred_exprs(p, a)),

EXTRA) }

kwargs[asdl_seq*]:

| a=','.kwarg_or_starred+ ',' b=','.kwarg_or_double_starred+ { _PyPegen_join_sequences(p, a, b) }

| ','.kwarg_or_starred+

| ','.kwarg_or_double_starred+

starred_expression[expr_ty]:

| '*' a=expression { _PyAST_Starred(a, Load, EXTRA) }

kwarg_or_starred[KeywordOrStarred*]:

| invalid_kwarg

| a=NAME '=' b=expression {

_PyPegen_keyword_or_starred(p, CHECK(keyword_ty, _PyAST_keyword(a->v.Name.id, b, EXTRA)), 1) }

| a=starred_expression { _PyPegen_keyword_or_starred(p, a, 0) }

kwarg_or_double_starred[KeywordOrStarred*]:

| invalid_kwarg

| a=NAME '=' b=expression {

_PyPegen_keyword_or_starred(p, CHECK(keyword_ty, _PyAST_keyword(a->v.Name.id, b, EXTRA)), 1) }

| '**' a=expression { _PyPegen_keyword_or_starred(p, CHECK(keyword_ty, _PyAST_keyword(NULL, a, EXTRA)), 1) }

# NOTE: star_targets may contain *bitwise_or, targets may not.

star_targets[expr_ty]:

| a=star_target !',' { a }

| a=star_target b=(',' c=star_target { c })* [','] {

_PyAST_Tuple(CHECK(asdl_expr_seq*, _PyPegen_seq_insert_in_front(p, a, b)), Store, EXTRA) }

star_targets_list_seq[asdl_expr_seq*]: a[asdl_expr_seq*]=','.star_target+ [','] { a }

star_targets_tuple_seq[asdl_expr_seq*]:

| a=star_target b=(',' c=star_target { c })+ [','] { (asdl_expr_seq*) _PyPegen_seq_insert_in_front(p, a, b) }

| a=star_target ',' { (asdl_expr_seq*) _PyPegen_singleton_seq(p, a) }

star_target[expr_ty] (memo):

| '*' a=(!'*' star_target) {

_PyAST_Starred(CHECK(expr_ty, _PyPegen_set_expr_context(p, a, Store)), Store, EXTRA) }

| target_with_star_atom

target_with_star_atom[expr_ty] (memo):

| a=t_primary '.' b=NAME !t_lookahead { _PyAST_Attribute(a, b->v.Name.id, Store, EXTRA) }

| a=t_primary '[' b=slices ']' !t_lookahead { _PyAST_Subscript(a, b, Store, EXTRA) }

| star_atom

star_atom[expr_ty]:

| a=NAME { _PyPegen_set_expr_context(p, a, Store) }

| '(' a=target_with_star_atom ')' { _PyPegen_set_expr_context(p, a, Store) }

| '(' a=[star_targets_tuple_seq] ')' { _PyAST_Tuple(a, Store, EXTRA) }

| '[' a=[star_targets_list_seq] ']' { _PyAST_List(a, Store, EXTRA) }

single_target[expr_ty]:

| single_subscript_attribute_target

| a=NAME { _PyPegen_set_expr_context(p, a, Store) }

| '(' a=single_target ')' { a }

single_subscript_attribute_target[expr_ty]:

| a=t_primary '.' b=NAME !t_lookahead { _PyAST_Attribute(a, b->v.Name.id, Store, EXTRA) }

| a=t_primary '[' b=slices ']' !t_lookahead { _PyAST_Subscript(a, b, Store, EXTRA) }

del_targets[asdl_expr_seq*]: a[asdl_expr_seq*]=','.del_target+ [','] { a }

del_target[expr_ty] (memo):

| a=t_primary '.' b=NAME !t_lookahead { _PyAST_Attribute(a, b->v.Name.id, Del, EXTRA) }

| a=t_primary '[' b=slices ']' !t_lookahead { _PyAST_Subscript(a, b, Del, EXTRA) }

| del_t_atom

del_t_atom[expr_ty]:

| a=NAME { _PyPegen_set_expr_context(p, a, Del) }

| '(' a=del_target ')' { _PyPegen_set_expr_context(p, a, Del) }

| '(' a=[del_targets] ')' { _PyAST_Tuple(a, Del, EXTRA) }

| '[' a=[del_targets] ']' { _PyAST_List(a, Del, EXTRA) }

t_primary[expr_ty]:

| a=t_primary '.' b=NAME &t_lookahead { _PyAST_Attribute(a, b->v.Name.id, Load, EXTRA) }

| a=t_primary '[' b=slices ']' &t_lookahead { _PyAST_Subscript(a, b, Load, EXTRA) }

| a=t_primary b=genexp &t_lookahead {

_PyAST_Call(a, CHECK(asdl_expr_seq*, (asdl_expr_seq*)_PyPegen_singleton_seq(p, b)), NULL, EXTRA) }

| a=t_primary '(' b=[arguments] ')' &t_lookahead {

_PyAST_Call(a,

(b) ? ((expr_ty) b)->v.Call.args : NULL,

(b) ? ((expr_ty) b)->v.Call.keywords : NULL,

EXTRA) }

| a=atom &t_lookahead { a }

t_lookahead: '(' | '[' | '.'

# From here on, there are rules for invalid syntax with specialised error messages

invalid_arguments:

| a=args ',' '*' { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "iterable argument unpacking follows keyword argument unpacking") }

| a=expression b=for_if_clauses ',' [args | expression for_if_clauses] {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, _PyPegen_get_last_comprehension_item(PyPegen_last_item(b, comprehension_ty)), "Generator expression must be parenthesized") }

| a=NAME b='=' expression for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "invalid syntax. Maybe you meant '==' or ':=' instead of '='?")}

| a=args b=for_if_clauses { _PyPegen_nonparen_genexp_in_call(p, a, b) }

| args ',' a=expression b=for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, _PyPegen_get_last_comprehension_item(PyPegen_last_item(b, comprehension_ty)), "Generator expression must be parenthesized") }

| a=args ',' args { _PyPegen_arguments_parsing_error(p, a) }

invalid_kwarg:

| a[Token*]=('True'|'False'|'None') b='=' {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "cannot assign to %s", PyBytes_AS_STRING(a->bytes)) }

| a=NAME b='=' expression for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "invalid syntax. Maybe you meant '==' or ':=' instead of '='?")}

| !(NAME '=') a=expression b='=' {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(

a, b, "expression cannot contain assignment, perhaps you meant \"==\"?") }

# IMPORTANT: Note that the "_without_invalid" suffix causes the rule to not call invalid rules under it

expression_without_invalid[expr_ty]:

| a=disjunction 'if' b=disjunction 'else' c=expression { _PyAST_IfExp(b, a, c, EXTRA) }

| disjunction

| lambdef

invalid_legacy_expression:

| a=NAME !'(' b=star_expressions {

_PyPegen_check_legacy_stmt(p, a) ? RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b,

"Missing parentheses in call to '%U'. Did you mean %U(...)?", a->v.Name.id, a->v.Name.id) : NULL}

invalid_expression:

# !(NAME STRING) is not matched so we don't show this error with some invalid string prefixes like: kf"dsfsdf"

# Soft keywords need to also be ignored because they can be parsed as NAME NAME

| !(NAME STRING | SOFT_KEYWORD) a=disjunction b=expression_without_invalid {

_PyPegen_check_legacy_stmt(p, a) ? NULL : p->tokens[p->mark-1]->level == 0 ? NULL :

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "invalid syntax. Perhaps you forgot a comma?") }

| a=disjunction 'if' b=disjunction !('else'|':') { RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "expected 'else' after 'if' expression") }

invalid_named_expression(memo):

| a=expression ':=' expression {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(

a, "cannot use assignment expressions with %s", _PyPegen_get_expr_name(a)) }

| a=NAME '=' b=bitwise_or !('='|':=') {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "invalid syntax. Maybe you meant '==' or ':=' instead of '='?") }

| !(list|tuple|genexp|'True'|'None'|'False') a=bitwise_or b='=' bitwise_or !('='|':=') {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "cannot assign to %s here. Maybe you meant '==' instead of '='?",

_PyPegen_get_expr_name(a)) }

invalid_assignment:

| a=invalid_ann_assign_target ':' expression {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(

a,

"only single target (not %s) can be annotated",

_PyPegen_get_expr_name(a)

)}

| a=star_named_expression ',' star_named_expressions* ':' expression {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "only single target (not tuple) can be annotated") }

| a=expression ':' expression {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "illegal target for annotation") }

| (star_targets '=')* a=star_expressions '=' {

RAISE_SYNTAX_ERROR_INVALID_TARGET(STAR_TARGETS, a) }

| (star_targets '=')* a=yield_expr '=' { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "assignment to yield expression not possible") }

| a=star_expressions augassign (yield_expr | star_expressions) {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(

a,

"'%s' is an illegal expression for augmented assignment",

_PyPegen_get_expr_name(a)

)}

invalid_ann_assign_target[expr_ty]:

| list

| tuple

| '(' a=invalid_ann_assign_target ')' { a }

invalid_del_stmt:

| 'del' a=star_expressions {

RAISE_SYNTAX_ERROR_INVALID_TARGET(DEL_TARGETS, a) }

invalid_block:

| NEWLINE !INDENT { RAISE_INDENTATION_ERROR("expected an indented block") }

invalid_comprehension:

| ('[' | '(' | '{') a=starred_expression for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "iterable unpacking cannot be used in comprehension") }

| ('[' | '{') a=star_named_expression ',' b=star_named_expressions for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, PyPegen_last_item(b, expr_ty),

"did you forget parentheses around the comprehension target?") }

| ('[' | '{') a=star_named_expression b=',' for_if_clauses {

RAISE_SYNTAX_ERROR_KNOWN_RANGE(a, b, "did you forget parentheses around the comprehension target?") }

invalid_dict_comprehension:

| '{' a='**' bitwise_or for_if_clauses '}' {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "dict unpacking cannot be used in dict comprehension") }

invalid_parameters:

| param_no_default* invalid_parameters_helper a=param_no_default {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "non-default argument follows default argument") }

invalid_parameters_helper: # This is only there to avoid type errors

| a=slash_with_default { _PyPegen_singleton_seq(p, a) }

| param_with_default+

invalid_lambda_parameters:

| lambda_param_no_default* invalid_lambda_parameters_helper a=lambda_param_no_default {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "non-default argument follows default argument") }

invalid_lambda_parameters_helper:

| a=lambda_slash_with_default { _PyPegen_singleton_seq(p, a) }

| lambda_param_with_default+

invalid_star_etc:

| a='*' (')' | ',' (')' | '**')) { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "named arguments must follow bare *") }

| '*' ',' TYPE_COMMENT { RAISE_SYNTAX_ERROR("bare * has associated type comment") }

invalid_lambda_star_etc:

| '*' (':' | ',' (':' | '**')) { RAISE_SYNTAX_ERROR("named arguments must follow bare *") }

invalid_double_type_comments:

| TYPE_COMMENT NEWLINE TYPE_COMMENT NEWLINE INDENT {

RAISE_SYNTAX_ERROR("Cannot have two type comments on def") }

invalid_with_item:

| expression 'as' a=expression &(',' | ')' | ':') {

RAISE_SYNTAX_ERROR_INVALID_TARGET(STAR_TARGETS, a) }

invalid_for_target:

| ASYNC? 'for' a=star_expressions {

RAISE_SYNTAX_ERROR_INVALID_TARGET(FOR_TARGETS, a) }

invalid_group:

| '(' a=starred_expression ')' {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "cannot use starred expression here") }

| '(' a='**' expression ')' {

RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "cannot use double starred expression here") }

invalid_import_from_targets:

| import_from_as_names ',' NEWLINE {

RAISE_SYNTAX_ERROR("trailing comma not allowed without surrounding parentheses") }

invalid_with_stmt:

| [ASYNC] 'with' ','.(expression ['as' star_target])+ NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }

| [ASYNC] 'with' '(' ','.(expressions ['as' star_target])+ ','? ')' NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }

invalid_with_stmt_indent:

| [ASYNC] a='with' ','.(expression ['as' star_target])+ ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'with' statement on line %d", a->lineno) }

| [ASYNC] a='with' '(' ','.(expressions ['as' star_target])+ ','? ')' ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'with' statement on line %d", a->lineno) }

invalid_try_stmt:

| a='try' ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'try' statement on line %d", a->lineno) }

| 'try' ':' block !('except' | 'finally') { RAISE_SYNTAX_ERROR("expected 'except' or 'finally' block") }

invalid_except_stmt:

| 'except' a=expression ',' expressions ['as' NAME ] ':' {

RAISE_SYNTAX_ERROR_STARTING_FROM(a, "multiple exception types must be parenthesized") }

| a='except' expression ['as' NAME ] NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }

| a='except' NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }

invalid_finally_stmt:

| a='finally' ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'finally' statement on line %d", a->lineno) }

invalid_except_stmt_indent:

| a='except' expression ['as' NAME ] ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'except' statement on line %d", a->lineno) }

| a='except' ':' NEWLINE !INDENT { RAISE_INDENTATION_ERROR("expected an indented block after 'except' statement on line %d", a->lineno) }

invalid_match_stmt:

| "match" subject_expr NEWLINE { CHECK_VERSION(void*, 10, "Pattern matching is", RAISE_SYNTAX_ERROR("expected ':'") ) }

| a="match" subject=subject_expr ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'match' statement on line %d", a->lineno) }

invalid_case_block:

| "case" patterns guard? NEWLINE { RAISE_SYNTAX_ERROR("expected ':'") }

| a="case" patterns guard? ':' NEWLINE !INDENT {

RAISE_INDENTATION_ERROR("expected an indented block after 'case' statement on line %d", a->lineno) }

invalid_as_pattern:

| or_pattern 'as' a="_" { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "cannot use '_' as a target") }

| or_pattern 'as' !NAME a=expression { RAISE_SYNTAX_ERROR_KNOWN_LOCATION(a, "invalid pattern target") }

invalid_class_pattern:

| name_or_attr '(' a=invalid_class_argument_pattern { RAISE_SYNTAX_ERROR_KNOWN_RANGE(

PyPegen_first_item(a, pattern_ty),

PyPegen_last_item(a, pattern_ty),

"positional patterns follow keyword patterns") }

invalid_class_argument_pattern[asdl_pattern_seq*]:

| [positional_patterns ','] keyword_patterns ',' a=positional_patterns { a }