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Index ¶
- type ArrayLiteral
- type BlockStatement
- type Boolean
- type CallExpression
- type Expression
- type ExpressionStatement
- type FunctionLiteral
- type HashLiteral
- type Identifier
- type IfExpression
- type IndexExpression
- type InfixExpression
- type IntegerLiteral
- type LetStatement
- type Node
- type PrefixExpression
- type Program
- type ReturnStatement
- type Statement
- type StringLiteral
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type ArrayLiteral ¶
type ArrayLiteral struct {
Token token.Token // the "[" token
Elements []Expression
}
ArrayLiteral is used to construct an ast.Node for array literals ([1,2,3]). Parsing the tokens of an array literal should return an ArrayLiteral struct. ArrayLiteral is a valid expression node within the abstract-syntax tree.
func (*ArrayLiteral) String ¶
func (al *ArrayLiteral) String() string
String builds the entire ArrayLiteral as a string, first by stringifying all its elments, then building the string with the ArrayLiteral expected components
func (*ArrayLiteral) TokenLiteral ¶
func (al *ArrayLiteral) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the opening bracket of the array
type BlockStatement ¶
BlockStatement holds the necessary information to construct a statement(s) that exist within an IfExpression or Function Literal
func (*BlockStatement) String ¶
func (bs *BlockStatement) String() string
String will construct the entire BlockStatement as a string by iterating through and stringifying all its statements. The statements can be any combination of LET, RETURN or ExpressionStatements
func (*BlockStatement) TokenLiteral ¶
func (bs *BlockStatement) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the "{" token
type Boolean ¶
Boolean holds a Token field (Token{TokenType, Literal}) for the boolean and a Value field for the actual bool value
func (*Boolean) TokenLiteral ¶
TokenLiteral returns the literal value (Token.Literal) for the the Boolean
type CallExpression ¶
type CallExpression struct {
Token token.Token // The "(" token
Function Expression // Identifier of Function Literal
Arguments []Expression // The list of expressions that are arguments to the function call
}
CallExpression consist of an expression that results in a function when evaluated and a list of expressions that are the arguments of this function call
func (*CallExpression) String ¶
func (ce *CallExpression) String() string
String builds the entire CallExpression as a string, first by stringifying all its arguments, then building the string with the CallExpressions expected components
func (*CallExpression) TokenLiteral ¶
func (ce *CallExpression) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the "(" token
type Expression ¶
type Expression interface {
Node
// contains filtered or unexported methods
}
Expression is the interface that embeds the Node interface and the expressionNode method
expressionNode() is a dummy method that does not do anything practical at the moment, it simply distinguishes the Expression interface
type ExpressionStatement ¶
type ExpressionStatement struct {
Token token.Token // the first token of the expression
Expression Expression
}
ExpressionStatement holds a Token field and an Expression field for the expression. It implements the Node and Statement interfaces.
func (*ExpressionStatement) String ¶
func (es *ExpressionStatement) String() string
String constructs the entire ExpressionStatement node as a string
func (*ExpressionStatement) TokenLiteral ¶
func (es *ExpressionStatement) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the first token in the expression
type FunctionLiteral ¶
type FunctionLiteral struct {
Token token.Token // The 'fn' token
Parameters []*Identifier // The parameters of the function
Body *BlockStatement // The collection of statements in the body of the function
Name string // The name the function is bound to
}
FunctionLiteral holds the necessary information to construct a function-literal expression
func (*FunctionLiteral) String ¶
func (fl *FunctionLiteral) String() string
String builds the entire FunctionLiteral as a string, first by stringifying all its params, then building the string with the FunctionLiterals expected components
func (*FunctionLiteral) TokenLiteral ¶
func (fl *FunctionLiteral) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the "fn" token
type HashLiteral ¶
type HashLiteral struct {
Token token.Token // the '{' token
Pairs map[Expression]Expression // the key value pairs of the hash
}
HashLiteral is used to construct an ast.Node for hash literals ({ "a": 1 }) Parsing the tokens of a hash literal should return an HashLiteral struct. HashLiteral is a valid expression node within the abstract-syntax tree.
func (*HashLiteral) String ¶
func (hl *HashLiteral) String() string
String builds the entire HashLiteral as a string. It stringifies the key value pairs, then builds the string with the String expected components
func (*HashLiteral) TokenLiteral ¶
func (hl *HashLiteral) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the opening brace of the hash literal
type Identifier ¶
type Identifier struct {
Token token.Token // the token.IDENT token
// Value is used to represent the name in a variable binding x in `let x = 5`,
Value string
}
Identifier holds the identifier of a binding eg: x in `let x = 5` and implements the Expression interface
func (*Identifier) String ¶
func (i *Identifier) String() string
String() returns the identifier's name value (x in let x = 5)
func (*Identifier) TokenLiteral ¶
func (i *Identifier) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for a token of type Token.IDENT
type IfExpression ¶
type IfExpression struct {
Token token.Token // The 'if' token
Condition Expression // The condition to be evalated
Consequence *BlockStatement // The collection of statements which is a direct result of the passing Condition
Alternative *BlockStatement // The alternative statements should the condition not pass
}
IfExpression holds the necessary information to construct an if-expression
func (*IfExpression) String ¶
func (ie *IfExpression) String() string
String will contruct the entire IfExpression as a string
func (*IfExpression) TokenLiteral ¶
func (ie *IfExpression) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the the if token
type IndexExpression ¶
type IndexExpression struct {
Token token.Token // The [ Token
Left Expression
Index Expression
}
IndexExpression is used to construct an ast.Node for index operator expressions ([1, 2, 3][1]) Parsing the tokens of an index operator expression should return an IndexExpression struct. IndexExpression is a valid expression node within the abstract-syntax tree.
func (*IndexExpression) String ¶
func (ie *IndexExpression) String() string
String builds the entire IndexExpression as a string. It stringifies the array and index, then builds the string with the IndexExpression expected components
func (*IndexExpression) TokenLiteral ¶
func (ie *IndexExpression) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the opening bracket of the index operation
type InfixExpression ¶
type InfixExpression struct {
Token token.Token
Left Expression
Operator string
Right Expression
}
PrefixExpression holds a Token field for the input, Left contains the expression to the right of the operator. Operator is a string that contains either "-" or "!" and Right contains the expression to the right of the operator.
func (*InfixExpression) String ¶
func (ie *InfixExpression) String() string
String constructs a string for the InfixExpression, explicitly adding paranthesis around the constructed string to distinguish it from other expressions
func (*InfixExpression) TokenLiteral ¶
func (ie *InfixExpression) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the the InfixExpression input
type IntegerLiteral ¶
IntegerLiteral holds a Token field (Token{TokenType, Literal}) for the integer and a Value field for the actual integer value
func (*IntegerLiteral) String ¶
func (il *IntegerLiteral) String() string
String constructs the integer value as a string
func (*IntegerLiteral) TokenLiteral ¶
func (il *IntegerLiteral) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the the integer
type LetStatement ¶
type LetStatement struct {
Token token.Token // the token.LET token
Name *Identifier // Name holds the identifer of the binding
// Value is the expression that produces the value eg: 5 in `let x = 5`.
// Coincidentally, it can also be an identifier for an expression in a different statement
// eg: valueProducingIdentifier in `let x = valueProducingIdentifier` is an identifier
// for a different statement eg: `let valueProducingIdentifier = 5`
// Therefore in this statement, `let x = valueProducingIdentifier`, valueProducingIdentifer
// is an identifier that serves as an expression - it produces a value
Value Expression
}
LetStatement holds the name and value for a let statement
func (*LetStatement) String ¶
func (ls *LetStatement) String() string
String constructs the entire LetStatement node as a string
func (*LetStatement) TokenLiteral ¶
func (ls *LetStatement) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for a token of type Token.LET
type Node ¶
Node is the interface that wraps TokenLiteral method
TokenLiteral() should return a token's literal value (Token.Literal) in a Node String() should return the AST node as a string
type PrefixExpression ¶
type PrefixExpression struct {
Token token.Token
Operator string
Right Expression
}
PrefixExpression holds a Token field for the input, Operator is a string that contains either "-" or "!" and Right contains the expression to the right of the operator.
func (*PrefixExpression) String ¶
func (pe *PrefixExpression) String() string
String constructs a string for the PrefixExpression, explicitly adding paranthesis around the constructed string to distinguish it from other expressions
func (*PrefixExpression) TokenLiteral ¶
func (pe *PrefixExpression) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the the PrefixExpression input
type Program ¶
type Program struct {
Statements []Statement // Statements are just a slice of AST nodes
}
Program serves as the root node of every AST a parser produces.
func (*Program) String ¶
String creates a buffer and writes the return value of each statement's String() method to it. Finally it returns the buffer as a string.
func (*Program) TokenLiteral ¶
TokenLiteral returns the token literal for the first statement in the program
type ReturnStatement ¶
type ReturnStatement struct {
Token token.Token // the token.RETURN token
ReturnValue Expression
}
ReturnStatement holds a Token field for the return token and a ReturnValue field for the expression that's to be returned
func (*ReturnStatement) String ¶
func (rs *ReturnStatement) String() string
String constructs the entire ReturnStatement node as a string
func (*ReturnStatement) TokenLiteral ¶
func (rs *ReturnStatement) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for a token of type token.RETURN
type Statement ¶
type Statement interface {
Node
// contains filtered or unexported methods
}
Statement is the interface that embeds the Node interface and the statementNode method
statementNode() is a dummy method that does not do anything practical at the moment, it simply distinguishes the Statement interface
type StringLiteral ¶
StringLiteral holds a Token field (Token{TokenType, Literal}) for the lexed string and a Value field for the actual string value
func (*StringLiteral) String ¶
func (sl *StringLiteral) String() string
String returns the literal value (Token.Literal) for the the StringLiteral
func (*StringLiteral) TokenLiteral ¶
func (sl *StringLiteral) TokenLiteral() string
TokenLiteral returns the literal value (Token.Literal) for the string
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