aboutsummaryrefslogtreecommitdiffstats
path: root/docs/grammar.txt
blob: 3d2c9bc37e8ff19c3cce31041620835cad5034cd (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
SourceUnit = (PragmaDirective | ImportDirective | ContractDefinition)*

// Pragma actually parses anything up to the trailing ';' to be fully forward-compatible.
PragmaDirective = 'pragma' Identifier ([^;]+) ';'

ImportDirective = 'import' StringLiteral ('as' Identifier)? ';'
        | 'import' ('*' | Identifier) ('as' Identifier)? 'from' StringLiteral ';'
        | 'import' '{' Identifier ('as' Identifier)? ( ',' Identifier ('as' Identifier)? )* '}' 'from' StringLiteral ';'

ContractDefinition = ( 'contract' | 'library' | 'interface' ) Identifier
                     ( 'is' InheritanceSpecifier (',' InheritanceSpecifier )* )?
                     '{' ContractPart* '}'

ContractPart = StateVariableDeclaration | UsingForDeclaration
             | StructDefinition | ModifierDefinition | FunctionDefinition | EventDefinition | EnumDefinition

InheritanceSpecifier = UserDefinedTypeName ( '(' Expression ( ',' Expression )* ')' )?

StateVariableDeclaration = TypeName ( 'public' | 'internal' | 'private' | 'constant' )* Identifier ('=' Expression)? ';'
UsingForDeclaration = 'using' Identifier 'for' ('*' | TypeName) ';'
StructDefinition = 'struct' Identifier '{'
                     ( VariableDeclaration ';' (VariableDeclaration ';')* ) '}'

ModifierDefinition = 'modifier' Identifier ParameterList? Block
ModifierInvocation = Identifier ( '(' ExpressionList? ')' )?

FunctionDefinition = 'function' Identifier? ParameterList
                     ( ModifierInvocation | StateMutability | 'external' | 'public' | 'internal' | 'private' )*
                     ( 'returns' ParameterList )? ( ';' | Block )
EventDefinition = 'event' Identifier EventParameterList 'anonymous'? ';'

EnumValue = Identifier
EnumDefinition = 'enum' Identifier '{' EnumValue? (',' EnumValue)* '}'

ParameterList = '(' ( Parameter (',' Parameter)* )? ')'
Parameter = TypeName StorageLocation? Identifier?

EventParameterList = '(' ( EventParameter (',' EventParameter )* )? ')'
EventParameter = TypeName 'indexed'? Identifier?

FunctionTypeParameterList = '(' ( FunctionTypeParameter (',' FunctionTypeParameter )* )? ')'
FunctionTypeParameter = TypeName StorageLocation?

// semantic restriction: mappings and structs (recursively) containing mappings
// are not allowed in argument lists
VariableDeclaration = TypeName StorageLocation? Identifier

TypeName = ElementaryTypeName
         | UserDefinedTypeName
         | Mapping
         | ArrayTypeName
         | FunctionTypeName
         | ( 'address' 'payable' )

UserDefinedTypeName = Identifier ( '.' Identifier )*

Mapping = 'mapping' '(' ElementaryTypeName '=>' TypeName ')'
ArrayTypeName = TypeName '[' Expression? ']'
FunctionTypeName = 'function' FunctionTypeParameterList ( 'internal' | 'external' | StateMutability )*
                   ( 'returns' FunctionTypeParameterList )?
StorageLocation = 'memory' | 'storage' | 'calldata'
StateMutability = 'pure' | 'view' | 'payable'

Block = '{' Statement* '}'
Statement = IfStatement | WhileStatement | ForStatement | Block | InlineAssemblyStatement |
            ( DoWhileStatement | PlaceholderStatement | Continue | Break | Return |
              Throw | EmitStatement | SimpleStatement ) ';'

ExpressionStatement = Expression
IfStatement = 'if' '(' Expression ')' Statement ( 'else' Statement )?
WhileStatement = 'while' '(' Expression ')' Statement
PlaceholderStatement = '_'
SimpleStatement = VariableDefinition | ExpressionStatement
ForStatement = 'for' '(' (SimpleStatement)? ';' (Expression)? ';' (ExpressionStatement)? ')' Statement
InlineAssemblyStatement = 'assembly' StringLiteral? AssemblyBlock
DoWhileStatement = 'do' Statement 'while' '(' Expression ')'
Continue = 'continue'
Break = 'break'
Return = 'return' Expression?
Throw = 'throw'
EmitStatement = 'emit' FunctionCall
VariableDefinition = (VariableDeclaration | '(' VariableDeclaration? (',' VariableDeclaration? )* ')' ) ( '=' Expression )?

// Precedence by order (see github.com/ethereum/solidity/pull/732)
Expression
  = Expression ('++' | '--')
  | NewExpression
  | IndexAccess
  | MemberAccess
  | FunctionCall
  | '(' Expression ')'
  | ('!' | '~' | 'delete' | '++' | '--' | '+' | '-') Expression
  | Expression '**' Expression
  | Expression ('*' | '/' | '%') Expression
  | Expression ('+' | '-') Expression
  | Expression ('<<' | '>>') Expression
  | Expression '&' Expression
  | Expression '^' Expression
  | Expression '|' Expression
  | Expression ('<' | '>' | '<=' | '>=') Expression
  | Expression ('==' | '!=') Expression
  | Expression '&&' Expression
  | Expression '||' Expression
  | Expression '?' Expression ':' Expression
  | Expression ('=' | '|=' | '^=' | '&=' | '<<=' | '>>=' | '+=' | '-=' | '*=' | '/=' | '%=') Expression
  | PrimaryExpression

PrimaryExpression = BooleanLiteral
                  | NumberLiteral
                  | HexLiteral
                  | StringLiteral
                  | TupleExpression
                  | Identifier
                  | ElementaryTypeNameExpression

ExpressionList = Expression ( ',' Expression )*
NameValueList = Identifier ':' Expression ( ',' Identifier ':' Expression )*

FunctionCall = Expression '(' FunctionCallArguments ')'
FunctionCallArguments = '{' NameValueList? '}'
                      | ExpressionList?

NewExpression = 'new' TypeName
MemberAccess = Expression '.' Identifier
IndexAccess = Expression '[' Expression? ']'

BooleanLiteral = 'true' | 'false'
NumberLiteral = ( HexNumber | DecimalNumber ) (' ' NumberUnit)?
NumberUnit = 'wei' | 'szabo' | 'finney' | 'ether'
           | 'seconds' | 'minutes' | 'hours' | 'days' | 'weeks' | 'years'
HexLiteral = 'hex' ('"' ([0-9a-fA-F]{2})* '"' | '\'' ([0-9a-fA-F]{2})* '\'')
StringLiteral = '"' ([^"\r\n\\] | '\\' .)* '"'
Identifier = [a-zA-Z_$] [a-zA-Z_$0-9]*

HexNumber = '0x' [0-9a-fA-F]+
DecimalNumber = [0-9]+ ( '.' [0-9]* )? ( [eE] [0-9]+ )?

TupleExpression = '(' ( Expression? ( ',' Expression? )*  )? ')'
                | '[' ( Expression  ( ',' Expression  )*  )? ']'

ElementaryTypeNameExpression = ElementaryTypeName

ElementaryTypeName = 'address' | 'bool' | 'string' | Int | Uint | Byte | Fixed | Ufixed

Int = 'int' | 'int8' | 'int16' | 'int24' | 'int32' | 'int40' | 'int48' | 'int56' | 'int64' | 'int72' | 'int80' | 'int88' | 'int96' | 'int104' | 'int112' | 'int120' | 'int128' | 'int136' | 'int144' | 'int152' | 'int160' | 'int168' | 'int176' | 'int184' | 'int192' | 'int200' | 'int208' | 'int216' | 'int224' | 'int232' | 'int240' | 'int248' | 'int256'

Uint = 'uint' | 'uint8' | 'uint16' | 'uint24' | 'uint32' | 'uint40' | 'uint48' | 'uint56' | 'uint64' | 'uint72' | 'uint80' | 'uint88' | 'uint96' | 'uint104' | 'uint112' | 'uint120' | 'uint128' | 'uint136' | 'uint144' | 'uint152' | 'uint160' | 'uint168' | 'uint176' | 'uint184' | 'uint192' | 'uint200' | 'uint208' | 'uint216' | 'uint224' | 'uint232' | 'uint240' | 'uint248' | 'uint256'

Byte = 'byte' | 'bytes' | 'bytes1' | 'bytes2' | 'bytes3' | 'bytes4' | 'bytes5' | 'bytes6' | 'bytes7' | 'bytes8' | 'bytes9' | 'bytes10' | 'bytes11' | 'bytes12' | 'bytes13' | 'bytes14' | 'bytes15' | 'bytes16' | 'bytes17' | 'bytes18' | 'bytes19' | 'bytes20' | 'bytes21' | 'bytes22' | 'bytes23' | 'bytes24' | 'bytes25' | 'bytes26' | 'bytes27' | 'bytes28' | 'bytes29' | 'bytes30' | 'bytes31' | 'bytes32'

Fixed = 'fixed' | ( 'fixed' [0-9]+ 'x' [0-9]+ )

Ufixed = 'ufixed' | ( 'ufixed' [0-9]+ 'x' [0-9]+ )


AssemblyBlock = '{' AssemblyStatement* '}'

AssemblyStatement = AssemblyBlock
                  | AssemblyFunctionDefinition
                  | AssemblyVariableDeclaration
                  | AssemblyAssignment
                  | AssemblyIf
                  | AssemblyExpression
                  | AssemblySwitch
                  | AssemblyForLoop
                  | AssemblyBreakContinue
AssemblyFunctionDefinition =
    'function' Identifier '(' AssemblyIdentifierList? ')'
    ( '->' AssemblyIdentifierList )? AssemblyBlock
AssemblyVariableDeclaration = 'let' AssemblyIdentifierList ( ':=' AssemblyExpression )?
AssemblyAssignment = AssemblyIdentifierList ':=' AssemblyExpression
AssemblyExpression = AssemblyFunctionCall | Identifier | Literal
AssemblyIf = 'if' AssemblyExpression AssemblyBlock
AssemblySwitch = 'switch' AssemblyExpression ( Case+ AssemblyDefault? | AssemblyDefault )
AssemblyCase = 'case' Literal AssemblyBlock
AssemblyDefault = 'default' AssemblyBlock
AssemblyForLoop = 'for' AssemblyBlock AssemblyExpression AssemblyBlock AssemblyBlock
AssemblyBreakContinue = 'break' | 'continue'
AssemblyFunctionCall = Identifier '(' ( AssemblyExpression ( ',' AssemblyExpression )* )? ')'

AssemblyIdentifierList = Identifier ( ',' Identifier )*