Name
SPVM::Document::Language::SyntaxParsing - Syntax Parsing in The SPVM Language
Description
This document describes syntax parsing in the SPVM language.
Syntax Parsing
Syntax parsing is the next step to build an AST after tokenization.
Syntax Parsing Rule
The rule of the syntax parsing of the SPVM language is described using GNU Bison syntax.
%token <opval> CLASS HAS METHOD OUR ENUM MY USE AS REQUIRE ALIAS ALLOW CURRENT_CLASS MUTABLE
%token <opval> ATTRIBUTE MAKE_READ_ONLY INTERFACE EVAL_ERROR_ID ARGS_WIDTH VERSION_DECL
%token <opval> IF UNLESS ELSIF ELSE FOR WHILE LAST NEXT SWITCH CASE DEFAULT BREAK EVAL
%token <opval> SYMBOL_NAME VAR_NAME CONSTANT EXCEPTION_VAR
%token <opval> UNDEF VOID BYTE SHORT INT LONG FLOAT DOUBLE STRING OBJECT TRUE FALSE END_OF_FILE
%token <opval> FATCAMMA RW RO WO INIT NEW OF BASIC_TYPE_ID EXTENDS SUPER
%token <opval> RETURN WEAKEN DIE WARN PRINT SAY CURRENT_CLASS_NAME UNWEAKEN '[' '{' '('
%type <opval> grammar
%type <opval> opt_classes classes class class_block version_decl
%type <opval> opt_definitions definitions definition
%type <opval> enumeration enumeration_block opt_enumeration_values enumeration_values enumeration_value
%type <opval> method anon_method opt_args args arg use require alias our has has_for_anon_list has_for_anon
%type <opval> opt_attributes attributes
%type <opval> opt_statements statements statement if_statement else_statement
%type <opval> for_statement while_statement foreach_statement
%type <opval> switch_statement case_statement case_statements opt_case_statements default_statement
%type <opval> block eval_block init_block switch_block if_require_statement
%type <opval> unary_operator binary_operator comparison_operator isa isa_error is_type is_error is_compile_type
%type <opval> call_method
%type <opval> array_access field_access weaken_field unweaken_field isweak_field convert array_length
%type <opval> assign inc dec allow can
%type <opval> new array_init die warn opt_extends
%type <opval> var_decl var interface union_type
%type <opval> operator opt_operators operators opt_operator logical_operator void_return_operator
%type <opval> field_name method_name alias_name is_read_only
%type <opval> type qualified_type basic_type array_type class_type opt_class_type
%type <opval> array_type_with_length ref_type return_type type_comment opt_type_comment
%right <opval> ASSIGN SPECIAL_ASSIGN
%left <opval> LOGICAL_OR
%left <opval> LOGICAL_AND
%left <opval> BIT_OR BIT_XOR
%left <opval> BIT_AND
%nonassoc <opval> NUMEQ NUMNE STREQ STRNE
%nonassoc <opval> NUMGT NUMGE NUMLT NUMLE STRGT STRGE STRLT STRLE ISA ISA_ERROR IS_TYPE IS_ERROR IS_COMPILE_TYPE NUMERIC_CMP STRING_CMP CAN
%left <opval> SHIFT
%left <opval> '+' '-' '.'
%left <opval> '*' DIVIDE DIVIDE_UNSIGNED_INT DIVIDE_UNSIGNED_LONG MODULO MODULO_UNSIGNED_INT MODULO_UNSIGNED_LONG
%right <opval> LOGICAL_NOT BIT_NOT '@' CREATE_REF DEREF PLUS MINUS CONVERT SCALAR STRING_LENGTH ISWEAK REFCNT TYPE_NAME COMPILE_TYPE_NAME DUMP NEW_STRING_LEN IS_READ_ONLY COPY
%nonassoc <opval> INC DEC
%left <opval> ARROW
grammar
: opt_classes
opt_classes
: /* Empty */
| classes
classes
: classes class
| class
class
: CLASS opt_class_type opt_extends class_block END_OF_FILE
| CLASS opt_class_type opt_extends ':' opt_attributes class_block END_OF_FILE
| CLASS opt_class_type opt_extends ';' END_OF_FILE
| CLASS opt_class_type opt_extends ':' opt_attributes ';' END_OF_FILE
opt_class_type
: /* Empty */
| class_type
opt_extends
: /* Empty */
| EXTENDS basic_type
class_block
: '{' opt_definitions '}'
opt_definitions
: /* Empty */
| definitions
definitions
: definitions definition
| definition
definition
: version_decl
| use
| alias
| allow
| interface
| init_block
| enumeration
| our
| has ';'
| method
init_block
: INIT block
version_decl
: VERSION_DECL CONSTANT ';'
use
: USE basic_type ';'
| USE basic_type AS alias_name ';'
require
: REQUIRE basic_type
alias
: ALIAS basic_type AS alias_name ';'
allow
: ALLOW basic_type ';'
interface
: INTERFACE basic_type ';'
enumeration
: opt_attributes ENUM enumeration_block
enumeration_block
: '{' opt_enumeration_values '}'
opt_enumeration_values
: /* Empty */
| enumeration_values
enumeration_values
: enumeration_values ',' enumeration_value
| enumeration_values ','
| enumeration_value
enumeration_value
: method_name
| method_name ASSIGN CONSTANT
our
: OUR VAR_NAME ':' opt_attributes qualified_type opt_type_comment ';'
has
: HAS field_name ':' opt_attributes qualified_type opt_type_comment
method
: opt_attributes METHOD method_name ':' return_type '(' opt_args ')' block
| opt_attributes METHOD method_name ':' return_type '(' opt_args ')' ';'
| opt_attributes METHOD ':' return_type '(' opt_args ')' block
| opt_attributes METHOD ':' return_type '(' opt_args ')' ';'
anon_method
: opt_attributes METHOD ':' return_type '(' opt_args ')' block
| '[' has_for_anon_list ']' opt_attributes METHOD ':' return_type '(' opt_args ')' block
opt_args
: /* Empty */
| args
args
: args ',' arg
| args ','
| arg
arg
: var ':' qualified_type opt_type_comment
| var ':' qualified_type opt_type_comment ASSIGN operator
has_for_anon_list
: has_for_anon_list ',' has_for_anon
| has_for_anon_list ','
| has_for_anon
has_for_anon
: HAS field_name ':' opt_attributes qualified_type opt_type_comment
| HAS field_name ':' opt_attributes qualified_type opt_type_comment ASSIGN operator
| var ':' opt_attributes qualified_type opt_type_comment
opt_attributes
: /* Empty */
| attributes
attributes
: attributes ATTRIBUTE
| ATTRIBUTE
opt_statements
: /* Empty */
| statements
statements
: statements statement
| statement
statement
: if_statement
| for_statement
| foreach_statement
| while_statement
| block
| switch_statement
| case_statement
| default_statement
| eval_block
| if_require_statement
| LAST ';'
| NEXT ';'
| BREAK ';'
| RETURN ';'
| RETURN operator ';'
| operator ';'
| void_return_operator ';'
| ';'
| die ';'
die
: DIE operator
| DIE
| DIE type operator
| DIE type
| DIE operator ',' operator
void_return_operator
: warn
| PRINT operator
| SAY operator
| weaken_field
| unweaken_field
| MAKE_READ_ONLY operator
warn
: WARN operator
| WARN
for_statement
: FOR '(' opt_operator ';' operator ';' opt_operator ')' block
foreach_statement
: FOR var_decl '(' '@' operator ')' block
| FOR var_decl '(' '@' '{' operator '}' ')' block
while_statement
: WHILE '(' operator ')' block
switch_statement
: SWITCH '(' operator ')' switch_block
switch_block
: '{' opt_case_statements '}'
| '{' opt_case_statements default_statement '}'
opt_case_statements
: /* Empty */
| case_statements
case_statements
: case_statements case_statement
| case_statement
case_statement
: CASE operator ':' block
| CASE operator ':'
default_statement
: DEFAULT ':' block
| DEFAULT ':'
if_require_statement
: IF '(' require ')' block
| IF '(' require ')' block ELSE block
if_statement
: IF '(' operator ')' block else_statement
| UNLESS '(' operator ')' block else_statement
else_statement
: /* NULL */
| ELSE block
| ELSIF '(' operator ')' block else_statement
block
: '{' opt_statements '}'
eval_block
: EVAL block
opt_operators
: /* Empty */
| operators
opt_operator
: /* Empty */
| operator
operator
: var
| EXCEPTION_VAR
| CONSTANT
| UNDEF
| call_method
| field_access
| array_access
| convert
| new
| array_init
| array_length
| var_decl
| unary_operator
| binary_operator
| assign
| inc
| dec
| '(' operators ')'
| CURRENT_CLASS_NAME
| isweak_field
| comparison_operator
| isa
| isa_error
| is_type
| is_error
| is_compile_type
| TRUE
| FALSE
| is_read_only
| can
| logical_operator
| BASIC_TYPE_ID type
| EVAL_ERROR_ID
| ARGS_WIDTH
operators
: operators ',' operator
| operators ','
| operator
unary_operator
: '+' operator %prec PLUS
| '-' operator %prec MINUS
| BIT_NOT operator
| REFCNT operator
| TYPE_NAME operator
| COMPILE_TYPE_NAME operator
| STRING_LENGTH operator
| DUMP operator
| DEREF var
| CREATE_REF operator
| NEW_STRING_LEN operator
| COPY operator
is_read_only
: IS_READ_ONLY operator
inc
: INC operator
| operator INC
dec
: DEC operator
| operator DEC
binary_operator
: operator '+' operator
| operator '-' operator
| operator '*' operator
| operator DIVIDE operator
| operator DIVIDE_UNSIGNED_INT operator
| operator DIVIDE_UNSIGNED_LONG operator
| operator MODULO operator
| operator MODULO_UNSIGNED_INT operator
| operator MODULO_UNSIGNED_LONG operator
| operator BIT_XOR operator
| operator BIT_AND operator
| operator BIT_OR operator
| operator SHIFT operator
| operator '.' operator
comparison_operator
: operator NUMEQ operator
| operator NUMNE operator
| operator NUMGT operator
| operator NUMGE operator
| operator NUMLT operator
| operator NUMLE operator
| operator NUMERIC_CMP operator
| operator STREQ operator
| operator STRNE operator
| operator STRGT operator
| operator STRGE operator
| operator STRLT operator
| operator STRLE operator
| operator STRING_CMP operator
isa
: operator ISA type
isa_error
: operator ISA_ERROR type
is_type
: operator IS_TYPE type
is_error
: operator IS_ERROR type
is_compile_type
: operator IS_COMPILE_TYPE type
logical_operator
: operator LOGICAL_OR operator
| operator LOGICAL_AND operator
| LOGICAL_NOT operator
assign
: operator ASSIGN operator
| operator SPECIAL_ASSIGN operator
new
: NEW basic_type
| NEW array_type_with_length
| anon_method
array_init
: '[' opt_operators ']'
| '{' operators '}'
| '{' '}'
convert
: '(' qualified_type ')' operator %prec CONVERT
| operator ARROW '(' qualified_type ')' %prec CONVERT
call_method
: CURRENT_CLASS SYMBOL_NAME '(' opt_operators ')'
| CURRENT_CLASS SYMBOL_NAME
| basic_type ARROW method_name '(' opt_operators ')'
| basic_type ARROW method_name
| operator ARROW method_name '(' opt_operators ')'
| operator ARROW method_name
| operator ARROW '(' opt_operators ')'
array_access
: operator ARROW '[' operator ']'
| array_access '[' operator ']'
| field_access '[' operator ']'
field_access
: operator ARROW '{' field_name '}'
| field_access '{' field_name '}'
| array_access '{' field_name '}'
weaken_field
: WEAKEN var ARROW '{' field_name '}'
unweaken_field
: UNWEAKEN var ARROW '{' field_name '}'
isweak_field
: ISWEAK var ARROW '{' field_name '}'
can
: operator CAN method_name
| operator CAN CONSTANT
array_length
: '@' operator
| '@' '{' operator '}'
| SCALAR '@' operator
| SCALAR '@' '{' operator '}'
var_decl
: MY var ':' qualified_type opt_type_comment
| MY var
var
: VAR_NAME
qualified_type
: type
| MUTABLE type {
type
: basic_type
| array_type
| ref_type
class_type
: basic_type
basic_type
: SYMBOL_NAME
| BYTE
| SHORT
| INT
| LONG
| FLOAT
| DOUBLE
| OBJECT
| STRING
ref_type
: basic_type '*'
array_type
: basic_type '[' ']'
| array_type '[' ']'
array_type_with_length
: basic_type '[' operator ']'
| array_type '[' operator ']'
return_type
: qualified_type opt_type_comment
| VOID
opt_type_comment
: /* Empty */
| type_comment
type_comment
: OF union_type
union_type
: union_type BIT_OR type
| type
field_name
: SYMBOL_NAME
method_name
: SYMBOL_NAME
alias_name
: SYMBOL_NAMESyntax Parsing Token
These are the values of the tokens used in "Syntax Parsing Rule".
| Tokens | Token Values |
|---|---|
| ALIAS | alias |
| ALLOW | allow |
| ARROW | -> |
| AS | as |
| ASSIGN | = |
| BIT_AND | & |
| BASIC_TYPE_ID | basic_type_id |
| BIT_NOT | ~ |
| BIT_OR | | |
| BIT_XOR | ^ |
| BREAK | break |
| BYTE | byte |
| CASE | case |
| CLASS | class |
| VAR_NAME | A variable name |
| COMPILE_TYPE_NAME | compile_type_name |
| CONSTANT | A literal |
| CONVERT | (TYPE_NAME) |
| COPY | copy |
| CURRENT_CLASS | & |
| CURRENT_CLASS_NAME | __PACKAGE__ |
| DEC | -- |
| DEFAULT | default |
| DEREF | $ |
| ATTRIBUTE | An attribute name |
| DIE | die |
| DIVIDE | / |
| DIVIDE_UNSIGNED_INT | div_uint |
| DIVIDE_UNSIGNED_LONG | div_ulong |
| DOUBLE | double |
| DUMP | dump |
| ELSE | else |
| ELSIF | elsif |
| END_OF_FILE | The end of the file |
| ENUM | enum |
| EVAL_ERROR_ID | eval_error_id |
| EXTENDS | extends |
| EVAL | eval |
| EXCEPTION_VAR | $@ |
| FATCAMMA | => |
| FLOAT | float |
| FOR | for |
| HAS | has |
| CAN | can |
| IF | if |
| INTERFACE | interface |
| INC | ++ |
| INIT | INIT |
| INT | int |
| ISA | isa |
| ISWEAK | isweak |
| IS_TYPE | is_type |
| IS_READ_ONLY | is_read_only |
| LAST | last |
| LENGTH | length |
| LOGICAL_AND | && |
| LOGICAL_NOT | ! |
| LOGICAL_OR | || |
| LONG | long |
| MAKE_READ_ONLY | make_read_only |
| METHOD | method |
| MINUS | - |
| MUTABLE | mutable |
| MY | my |
| SYMBOL_NAME | A symbol name |
| NEW | new |
| NEW_STRING_LEN | new_string_len |
| OF | of |
| NEXT | next |
| NUMEQ | == |
| NUMERIC_CMP | <=> |
| NUMGE | >= |
| NUMGT | > |
| NUMLE | <= |
| NUMLT | < |
| NUMNE | != |
| OBJECT | object |
| OUR | our |
| PLUS | + |
| REF | \ |
| TYPE_NAME | type_name |
| MODULO | % |
| MODULO_UNSIGNED_INT | mod_uint |
| MODULO_UNSIGNED_LONG | mod_ulong |
| REQUIRE | require |
| RETURN | return |
| RO | ro |
| RW | rw |
| SAY | say |
| SCALAR | scalar |
| SELF | self |
| SHIFT | << >> >>> |
| SHORT | short |
| SPECIAL_ASSIGN | += -= *= /= &= |= ^= %= <<= >>= >>>= .= |
| SRING_CMP | cmp |
| STREQ | eq |
| STRGE | ge |
| STRGT | gt |
| STRING | string |
| STRLE | le |
| STRLT | lt |
| STRNE | ne |
| SWITCH | switch |
| UNDEF | undef |
| UNLESS | unless |
| UNWEAKEN | unweaken |
| USE | use |
| VAR | var |
| VERSION | version |
| VOID | void |
| WARN | warn |
| WEAKEN | weaken |
| WHILE | while |
| WO | wo |
Operator Precidence
The operator precidence in the SPVM language is described using GNU Bison syntax.
The bottom is the highest precidence and the top is the lowest precidence.
%right <opval> ASSIGN SPECIAL_ASSIGN
%left <opval> LOGICAL_OR
%left <opval> LOGICAL_AND
%left <opval> BIT_OR BIT_XOR
%left <opval> BIT_AND
%nonassoc <opval> NUMEQ NUMNE STREQ STRNE
%nonassoc <opval> NUMGT NUMGE NUMLT NUMLE STRGT STRGE STRLT STRLE ISA ISA_ERROR IS_TYPE IS_ERROR IS_COMPILE_TYPE NUMERIC_CMP STRING_CMP CAN
%left <opval> SHIFT
%left <opval> '+' '-' '.'
%left <opval> '*' DIVIDE DIVIDE_UNSIGNED_INT DIVIDE_UNSIGNED_LONG MODULO MODULO_UNSIGNED_INT MODULO_UNSIGNED_LONG
%right <opval> LOGICAL_NOT BIT_NOT '@' CREATE_REF DEREF PLUS MINUS CONVERT SCALAR STRING_LENGTH ISWEAK REFCNT TYPE_NAME COMPILE_TYPE_NAME DUMP NEW_STRING_LEN IS_READ_ONLY COPY
%nonassoc <opval> INC DEC
%left <opval> ARROWThe operator precidence can be increased using ().
# a * b is calculated at first
a * b + c
# b + c is calculated at first
a * (b + c)See Also
Copyright & License
Copyright (c) 2023 Yuki Kimoto
MIT License