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grammar.y
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grammar.y
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class Opal::Grammar
token CLASS MODULE DEF UNDEF BEGIN RESCUE ENSURE END IF UNLESS
THEN ELSIF ELSE CASE WHEN WHILE UNTIL FOR BREAK NEXT
REDO RETRY IN DO DO_COND DO_BLOCK RETURN YIELD SUPER
SELF NIL TRUE FALSE AND OR NOT IF_MOD UNLESS_MOD WHILE_MOD
UNTIL_MOD RESCUE_MOD ALIAS DEFINED klBEGIN klEND LINE
FILE IDENTIFIER FID GVAR IVAR CONSTANT CVAR NTH_REF
BACK_REF STRING_CONTENT INTEGER FLOAT REGEXP_END '+@'
'-@' '-@NUM' '**' '<=>' '==' '===' '!=' '>=' '<=' '&&'
'||' '=~' '!~' '.' '..' '...' '[]' '[]=' '<<' '>>'
'::' '::@' OP_ASGN '=>' PAREN_BEG '(' ')' tLPAREN_ARG
ARRAY_BEG ']' tLBRACE tLBRACE_ARG SPLAT '*' '&@' '&'
'~' '%' '/' '+' '-' '<' '>' '|' '!' '^'
LCURLY '}' BACK_REF2 SYMBOL_BEG STRING_BEG XSTRING_BEG REGEXP_BEG
WORDS_BEG AWORDS_BEG STRING_DBEG STRING_DVAR STRING_END STRING
SYMBOL '\\n' '?' ':' ',' SPACE ';' LABEL LAMBDA LAMBEG DO_LAMBDA
prechigh
right '!' '~' '+@'
right '**'
right '-@NUM' '-@'
left '*' '/' '%'
left '+' '-'
left '<<' '>>'
left '&'
left '|' '^'
left '>' '>=' '<' '<='
nonassoc '<=>' '==' '===' '!=' '=~' '!~'
left '&&'
left '||'
nonassoc '..' '...'
right '?' ':'
left RESCUE_MOD
right '=' OP_ASGN
nonassoc DEFINED
right NOT
left OR AND
nonassoc IF_MOD UNLESS_MOD WHILE_MOD UNTIL_MOD
nonassoc tLBRACE_ARG
nonassoc LOWEST
preclow
rule
target:
compstmt
{
result = val[0]
}
bodystmt:
compstmt opt_rescue opt_else opt_ensure
{
result = new_body val[0], val[1], val[2], val[3]
}
compstmt:
stmts opt_terms
{
comp = new_compstmt val[0]
if comp and comp[0] == :begin and comp.size == 2
result = comp[1]
result.line = comp.line
else
result = comp
end
}
stmts:
none
{
result = new_block
}
| stmt
{
result = new_block val[0]
}
| stmts terms stmt
{
val[0] << val[2]
result = val[0]
}
stmt:
ALIAS fitem
{
@lex_state = :expr_fname
}
fitem
{
result = s(:alias, val[1], val[3])
}
| ALIAS GVAR GVAR
{
result = s(:valias, val[1].intern, val[2].intern)
}
| ALIAS GVAR BACK_REF
| ALIAS GVAR NTH_REF
{
result = s(:valias, val[1].intern, val[2].intern)
}
| UNDEF undef_list
{
result = val[1]
}
| stmt IF_MOD expr_value
{
result = new_if val[2], val[0], nil
}
| stmt UNLESS_MOD expr_value
{
result = new_if val[2], nil, val[0]
}
| stmt WHILE_MOD expr_value
{
result = s(:while, val[2], val[0], true)
}
| stmt UNTIL_MOD expr_value
{
result = s(:until, val[2], val[0], true)
}
| stmt RESCUE_MOD stmt
| klBEGIN LCURLY compstmt '}'
| klEND LCURLY compstmt '}'
| lhs '=' command_call
{
result = new_assign val[0], val[2]
}
| mlhs '=' command_call
{
result = s(:masgn, val[0], s(:to_ary, val[2]))
}
| var_lhs OP_ASGN command_call
{
result = new_op_asgn val[1].intern, val[0], val[2]
}
| primary_value '[@' aref_args ']' OP_ASGN command_call
# {
# result = OpAsgnNode.new(val[4], ArefNode.new(val[0], val[2]), val[5])
# }
| primary_value '.' IDENTIFIER OP_ASGN command_call
{
result = s(:op_asgn2, val[0], "#{val[2]}=".intern, val[3].intern, val[4])
}
| primary_value '.' CONSTANT OP_ASGN command_call
| primary_value '::' IDENTIFIER OP_ASGN command_call
| backref OP_ASGN command_call
| lhs '=' mrhs
{
result = new_assign val[0], s(:svalue, val[2])
}
| mlhs '=' arg_value
{
result = s(:masgn, val[0], s(:to_ary, val[2]))
}
| mlhs '=' mrhs
{
result = s(:masgn, val[0], val[2])
}
| expr
expr:
command_call
| expr AND expr
{
result = s(:and, val[0], val[2])
result.line = val[0].line
}
| expr OR expr
{
result = s(:or, val[0], val[2])
result.line = val[0].line
}
| NOT expr
{
result = s(:not, val[1])
result.line = val[1].line
}
| '!' command_call
{
result = s(:not, val[1])
}
| arg
expr_value:
expr
command_call:
command
| block_command
| RETURN call_args
{
args = val[1]
args = args[1] if args.size == 2
result = s(:return, args)
}
| BREAK call_args
{
args = val[1]
args = args[1] if args.size == 2
result = s(:break, args)
}
| NEXT call_args
{
args = val[1]
args = args[1] if args.size == 2
result = s(:next, args)
}
block_command:
block_call
| block_call '.' operation2 command_args
| block_call '::' operation2 command_args
cmd_brace_block:
tLBRACE_ARG opt_block_var compstmt '}'
command:
operation command_args =LOWEST
{
result = new_call nil, val[0].intern, val[1]
}
| operation command_args cmd_brace_block
| primary_value '.' operation2 command_args =LOWEST
{
result = new_call val[0], val[2].intern, val[3]
}
| primary_value '.' operation2 command_args cmd_brace_block
| primary_value '::' operation2 command_args =LOWEST
{
result = "result = ['call', val[0], val[2], val[3]];"
}
| primary_value '::' operation2 command_args cmd_brace_block
| SUPER command_args
{
result = new_super val[1]
}
| YIELD command_args
{
result = new_yield val[1]
}
mlhs:
mlhs_basic
{
result = val[0]
}
| PAREN_BEG mlhs_entry ')'
{
result = val[1]
}
mlhs_entry:
mlhs_basic
{
result = val[0]
}
| PAREN_BEG mlhs_entry ')'
{
result = val[1]
}
mlhs_basic:
mlhs_head
{
result = val[0]
}
| mlhs_head mlhs_item
{
result = val[0] << val[1]
}
| mlhs_head SPLAT mlhs_node
{
result = val[0] << s(:splat, val[2])
}
| mlhs_head SPLAT
{
result = val[0] << s(:splat)
}
| SPLAT mlhs_node
{
result = s(:array, s(:splat, val[1]))
}
| SPLAT
{
result = s(:array, s(:splat))
}
mlhs_item:
mlhs_node
{
result = val[0]
}
| PAREN_BEG mlhs_entry ')'
{
result = val[1]
}
mlhs_head:
mlhs_item ','
{
result = s(:array, val[0])
}
| mlhs_head mlhs_item ','
{
result = val[0] << val[1]
}
mlhs_node:
variable
{
result = new_assignable val[0]
}
| primary_value '[@' aref_args ']'
| primary_value '.' IDENTIFIER
| primary_value '::' IDENTIFIER
| primary_value '.' CONSTANT
| primary_value '::' CONSTANT
| '::@' CONSTANT
| backref
lhs:
variable
{
result = new_assignable val[0]
}
| primary_value '[@' aref_args ']'
{
args = val[2]
args[0] = :arglist if args[0] == :array
result = s(:attrasgn, val[0], :[]=, args)
}
| primary_value '.' IDENTIFIER
{
result = s(:attrasgn, val[0], "#{val[2]}=".intern, s(:arglist))
}
| primary_value '::' IDENTIFIER
{
result = s(:attrasgn, val[0], "#{val[2]}=".intern, s(:arglist))
}
| primary_value '.' CONSTANT
{
result = s(:attrasgn, val[0], "#{val[2]}=".intern, s(:arglist))
}
| primary_value '::' CONSTANT
| '::@' CONSTANT
| backref
cname:
CONSTANT
cpath:
'::@' cname
{
result = s(:colon3, val[1].intern)
}
| cname
{
result = val[0].intern
}
| primary_value '::' cname
{
result = s(:colon2, val[0], val[2].intern)
}
fname:
IDENTIFIER
| CONSTANT
| FID
| op
{
@lex_state = :expr_end
result = val[0]
}
| reswords
{
@lex_state = :expr_end
result = val[0]
}
fitem:
fname
{
result = s(:lit, val[0].intern)
}
| symbol
{
result = s(:lit, val[0])
}
undef_list:
fitem
{
result = s(:undef, val[0])
}
| undef_list ',' fitem
{
result = val[0] << val[2]
}
op:
'|' | '^' | '&' | '<=>' | '==' | '==='
| '=~' | '>' | '>=' | '<' | '<=' | '<<'
| '>>' | '+' | '-' | '*' | SPLAT | '/'
| '%' | '**' | '~' | '+@' | '-@' | '[]'
| '[]=' | BACK_REF2 | '!' | '!='
reswords:
LINE | FILE | klBEGIN | klEND | ALIAS | AND
| BEGIN | BREAK | CASE | CLASS | DEF | DEFINED
| DO | ELSE | ELSIF | END | ENSURE | FALSE
| FOR | IN | MODULE | NEXT | NIL | NOT
| OR | REDO | RESCUE | RETRY | RETURN | SELF
| SUPER | THEN | TRUE | UNDEF | WHEN | YIELD
| IF_MOD | UNLESS_MOD | WHILE_MOD | UNTIL_MOD | RESCUE_MOD
arg:
lhs '=' arg
{
result = new_assign val[0], val[2]
}
| lhs '=' arg RESCUE_MOD arg
| var_lhs OP_ASGN arg
{
result = new_op_asgn val[1].intern, val[0], val[2]
}
| primary_value '[@' aref_args ']' OP_ASGN arg
{
args = val[2]
args[0] = :arglist if args[0] == :array
result = s(:op_asgn1, val[0], val[2], val[4].intern, val[5])
result.line = val[0].line
}
| primary_value '.' IDENTIFIER OP_ASGN arg
{
result = s(:op_asgn2, val[0], "#{val[2]}=".intern, val[3].intern, val[4])
}
| primary_value '.' CONSTANT OP_ASGN arg
| primary_value '::' IDENTIFIER OP_ASGN arg
| primary_value '::' CONSTANT OP_ASGN arg
| '::@' CONSTANT OP_ASGN arg
| backref OP_ASGN arg
| arg '..' arg
{
result = s(:dot2, val[0], val[2])
result.line = val[0].line
}
| arg '...' arg
{
result = s(:dot3, val[0], val[2])
result.line = val[0].line
}
| arg '+' arg
{
result = s(:operator, :"+", val[0], val[2])
}
| arg '-' arg
{
result = s(:operator, :"-", val[0], val[2])
}
| arg '*' arg
{
result = s(:operator, :"*", val[0], val[2])
}
| arg '/' arg
{
result = s(:operator, :"/", val[0], val[2])
}
| arg '%' arg
{
result = new_call val[0], :"%", s(:arglist, val[2])
}
| arg '**' arg
{
result = new_call val[0], :"**", s(:arglist, val[2])
}
| '-@NUM' INTEGER '**' arg
| '-@NUM' FLOAT '**' arg
| '+@' arg
{
result = new_call val[1], :"+@", s(:arglist)
result = val[1] if val[1][0] == :lit and Numeric === val[1][1]
}
| '-@' arg
{
result = new_call val[1], :"-@", s(:arglist)
if val[1][0] == :lit and Numeric === val[1][1]
val[1][1] = -val[1][1]
result = val[1]
end
}
| arg '|' arg
{
result = new_call val[0], :"|", s(:arglist, val[2])
}
| arg '^' arg
{
result = new_call val[0], :"^", s(:arglist, val[2])
}
| arg '&' arg
{
result = new_call val[0], :"&", s(:arglist, val[2])
}
| arg '<=>' arg
{
result = new_call val[0], :"<=>", s(:arglist, val[2])
}
| arg '>' arg
{
result = new_call val[0], :">", s(:arglist, val[2])
}
| arg '>=' arg
{
result = new_call val[0], :">=", s(:arglist, val[2])
}
| arg '<' arg
{
result = new_call val[0], :"<", s(:arglist, val[2])
}
| arg '<=' arg
{
result = new_call val[0], :"<=", s(:arglist, val[2])
}
| arg '==' arg
{
result = new_call val[0], :"==", s(:arglist, val[2])
}
| arg '===' arg
{
result = new_call val[0], :"===", s(:arglist, val[2])
}
| arg '!=' arg
{
result = s(:not, new_call(val[0], :"==", s(:arglist, val[2])))
}
| arg '=~' arg
{
result = new_call val[0], :"=~", s(:arglist, val[2])
}
| arg '!~' arg
{
result = s(:not, new_call(val[0], :"=~", s(:arglist, val[2])))
}
| '!' arg
{
result = s(:not, val[1])
}
| '~' arg
{
result = new_call val[1], :"~", s(:arglist)
}
| arg '<<' arg
{
result = new_call val[0], :"<<", s(:arglist, val[2])
}
| arg '>>' arg
{
result = new_call val[0], :">>", s(:arglist, val[2])
}
| arg '&&' arg
{
result = s(:and, val[0], val[2])
result.line = val[0].line
}
| arg '||' arg
{
result = s(:or, val[0], val[2])
result.line = val[0].line
}
| DEFINED opt_nl arg
| arg '?' arg ':' arg
{
result = s(:if, val[0], val[2], val[4])
result.line = val[0].line
}
| primary
arg_value:
arg
aref_args:
none
{
result = nil
}
| args trailer
{
result = val[0]
}
| assocs trailer
{
result = s(:array, s(:hash, *val[0]))
}
paren_args:
'(' none ')'
{
result = nil
}
| '(' call_args opt_nl ')'
{
result = val[1]
}
| '(' block_call opt_nl ')'
| '(' args ',' block_call opt_nl ')'
opt_paren_args:
none
| paren_args
call_args:
command
{
result = s(:array, val[0])
}
| args opt_block_arg
{
result = val[0]
add_block_pass val[0], val[1]
}
| assocs opt_block_arg
{
result = s(:arglist, s(:hash, *val[0]))
add_block_pass result, val[1]
}
| args ',' assocs opt_block_arg
{
result = val[0]
result << s(:hash, *val[2])
}
| block_arg
{
result = s(:arglist)
add_block_pass result, val[0]
}
call_args2:
arg_value ',' args opt_block_arg
| block_arg
command_args:
{
cmdarg_push 1
}
open_args
{
cmdarg_pop
result = val[1]
}
open_args:
call_args
| tLPAREN_ARG ')'
{
result = nil
}
| tLPAREN_ARG call_args2 ')'
{
result = val[1]
}
block_arg:
'&@' arg_value
{
result = s(:block_pass, val[1])
}
opt_block_arg:
',' block_arg
{
result = val[1]
}
| none_block_pass
{
result = nil
}
args:
arg_value
{
result = s(:array, val[0])
}
| SPLAT arg_value
{
result = s(:array, s(:splat, val[1]))
}
| args ',' arg_value
{
result = val[0] << val[2]
}
| args ',' SPLAT arg_value
{
result = val[0] << s(:splat, val[3])
}
mrhs:
args ',' arg_value
{
val[0] << val[2]
result = val[0]
}
| args ',' SPLAT arg_value
| SPLAT arg_value
{
result = s(:splat, val[1])
}
primary:
literal
| strings
| xstring
| regexp
| words
| awords
| var_ref
| backref
| FID
| BEGIN
{
result = @line
}
bodystmt END
{
result = s(:begin, val[2])
result.line = val[1]
}
| tLPAREN_ARG expr opt_nl ')'
| PAREN_BEG compstmt ')'
{
result = val[1] || s(:nil)
}
| primary_value '::' CONSTANT
{
result = s(:colon2, val[0], val[2].intern)
}
| '::@' CONSTANT
{
result = s(:colon3, val[1])
}
| primary_value '[@' aref_args ']'
{
result = new_call val[0], :[], val[2]
}
| '[' aref_args ']'
{
result = val[1] || s(:array)
}
| '{' assoc_list '}'
{
result = s(:hash, *val[1])
}
| RETURN
{
result = s(:return)
}
| YIELD '(' call_args ')'
{
result = new_yield val[2]
}
| YIELD '(' ')'
{
result = s(:yield)
}
| YIELD
{
result = s(:yield)
}
| DEFINED opt_nl '(' expr ')'
{
result = s(:defined, val[3])
}
| operation brace_block
{
result = val[1]
result[1] = new_call(nil, val[0].intern, s(:arglist))
}
| method_call
| method_call brace_block
{
result = val[1]
result[1] = val[0]
}
| LAMBDA lambda
{
result = val[1]
}
| IF expr_value then compstmt if_tail END
{
result = new_if val[1], val[3], val[4]
}
| UNLESS expr_value then compstmt opt_else END
{
result = new_if val[1], val[4], val[3]
}
| WHILE
{
cond_push 1
result = @line
}
expr_value do
{
cond_pop
}
compstmt END
{
result = s(:while, val[2], val[5], true)
result.line = val[1]
}
| UNTIL
{
cond_push 1
result = @line
}
expr_value do
{
cond_pop
}
compstmt END
{
result = s(:until, val[2], val[5], true)
result.line = val[1]
}
| CASE expr_value opt_terms case_body END
{
result = s(:case, val[1], *val[3])
result.line = val[1].line
}
| CASE opt_terms case_body END
{
result = s(:case, nil, *val[2])
result.line = val[2].line
}
| CASE opt_terms ELSE compstmt END
{
result = s(:case, nil, val[3])
result.line = val[3].line
}
| FOR block_var IN
{
result = "this.cond_push(1);"
}
expr_value do
{
result = "this.cond_pop();"
}
compstmt END
| CLASS
{
result = @line
}
cpath superclass
{
# ...
}
bodystmt END
{
result = new_class val[2], val[3], val[5]
result.line = val[1]
result.end_line = @line
}
| CLASS '<<'
{
result = @line
}
expr term
{
# ...
}
bodystmt END
{
result = new_sclass val[3], val[6]
result.line = val[2]
}
| MODULE
{
result = @line
}
cpath
{
# ...
}
bodystmt END
{
result = new_module val[2], val[4]
result.line = val[1]
result.end_line = @line
}
| DEF fname
{
result = @scope_line
push_scope
}
f_arglist bodystmt END
{
result = new_defn val[2], val[1], val[3], val[4]
pop_scope
}
| DEF singleton dot_or_colon
{
# ..
}
fname
{
result = @scope_line
push_scope
}
f_arglist bodystmt END
{
result = new_defs val[5], val[1], val[4], val[6], val[7]
pop_scope
}
| BREAK
{
result = s(:break)
}
| NEXT
{
result = s(:next)
}
| REDO
{
result = s(:redo)
}
| RETRY
primary_value:
primary
then:
term
| ':'
| THEN
| term THEN
do:
term
| ':'
| DO_COND
lambda:
f_larglist lambda_body
{
call = new_call nil, :lambda, s(:arglist)
result = new_iter call, val[0], val[1]
}
f_larglist:
'(' block_var_args ')'
{
result = val[1]
}
| '(' ')'
{
result = nil
}
| block_var_args
| none
lambda_body:
LAMBEG compstmt '}'
{
result = val[1]
}
| DO_LAMBDA compstmt END
{
result = val[1]
}
if_tail:
opt_else
{
result = val[0]
}
| ELSIF
{
result = @line
}
expr_value then compstmt if_tail
{
result = s(:if, val[2], val[4], val[5])
result.line = val[1]
}
opt_else:
none
| ELSE compstmt
{
result = val[1]
}
block_var:
block_var_args
{
result = val[0]
}
block_var_args:
f_arg ',' f_block_optarg ',' f_rest_arg opt_f_block_arg
{