Documentation
¶
Overview ¶
Package ast contains the definitions of the abstract-syntax tree that our parse produces, and our interpreter executes.
Index ¶
- type ArrayLiteral
- type AssignStatement
- type BlockStatement
- type Boolean
- type CallExpression
- type CurrentArgsLiteral
- type DocStringLiteral
- type Expression
- type ExpressionStatement
- type FloatLiteral
- type ForLoopExpression
- type ForeachStatement
- type FunctionLiteral
- type HashLiteral
- type Identifier
- type IfExpression
- type ImportExpression
- type IndexExpression
- type InfixExpression
- type IntegerLiteral
- type LetStatement
- type MutableStatement
- type Node
- type NullLiteral
- type PostfixExpression
- type PrefixExpression
- type Program
- type ReturnStatement
- type SpreadLiteral
- 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 is the token
Token token.Token
// Elements holds the members of the array.
Elements []Expression
}
ArrayLiteral holds an inline array
func (*ArrayLiteral) String ¶
func (al *ArrayLiteral) String() string
String returns this object as a string.
func (*ArrayLiteral) TokenLiteral ¶
func (al *ArrayLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type AssignStatement ¶
type AssignStatement struct {
Token token.Token
Name *Identifier
Operator string
Value Expression
}
AssignStatement is generally used for a (let-less) assignment, such as "x = y", however we allow an operator to be stored ("=" in that example), such that we can do self-operations.
Specifically "x += y" is defined as an assignment-statement with the operator set to "+=". The same applies for "+=", "-=", "*=", and "/=".
func (*AssignStatement) String ¶
func (as *AssignStatement) String() string
String returns this object as a string.
func (*AssignStatement) TokenLiteral ¶
func (as *AssignStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type BlockStatement ¶
type BlockStatement struct {
// Token holds the actual token
Token token.Token
// Statements contain the set of statements within the block
Statements []Statement
}
BlockStatement holds a group of statements, which are treated as a block. (For example the body of an `if` expression.)
func (*BlockStatement) String ¶
func (bs *BlockStatement) String() string
String returns this object as a string.
func (*BlockStatement) TokenLiteral ¶
func (bs *BlockStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type Boolean ¶
type Boolean struct {
// Token holds the actual token
Token token.Token
// Value stores the bools' value: true, or false.
Value bool
}
Boolean holds a boolean type
func (*Boolean) TokenLiteral ¶
TokenLiteral returns the literal token.
type CallExpression ¶
type CallExpression struct {
// Token stores the literal token
Token token.Token
// Function is the function to be invoked.
Function Expression
// Arguments are the arguments to be applied
Arguments []Expression
}
CallExpression holds the invokation of a method-call.
func (*CallExpression) String ¶
func (ce *CallExpression) String() string
String returns this object as a string.
func (*CallExpression) TokenLiteral ¶
func (ce *CallExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type CurrentArgsLiteral ¶ added in v0.1.0
CurrentArgsLiteral holds the current args token
func (*CurrentArgsLiteral) String ¶ added in v0.1.0
func (cal *CurrentArgsLiteral) String() string
String returns a string representation of the literal
func (*CurrentArgsLiteral) TokenLiteral ¶ added in v0.1.0
func (cal *CurrentArgsLiteral) TokenLiteral() string
TokenLiteral returns the literal token
type DocStringLiteral ¶ added in v0.1.0
type DocStringLiteral struct {
// Token is the token
Token token.Token
// Value is the value of the string.
Value string
}
DocStringLiteral holds a string
func (*DocStringLiteral) String ¶ added in v0.1.0
func (sl *DocStringLiteral) String() string
String returns this object as a string.
func (*DocStringLiteral) TokenLiteral ¶ added in v0.1.0
func (sl *DocStringLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type Expression ¶
type Expression interface {
// Node is the node holding the expression.
Node
// contains filtered or unexported methods
}
Expression represents a single expression.
type ExpressionStatement ¶
type ExpressionStatement struct {
// Token is the literal token
Token token.Token
// Expression holds the expression
Expression Expression
}
ExpressionStatement is an expression
func (*ExpressionStatement) String ¶
func (es *ExpressionStatement) String() string
String returns this object as a string.
func (*ExpressionStatement) TokenLiteral ¶
func (es *ExpressionStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type FloatLiteral ¶
type FloatLiteral struct {
// Token is the literal token
Token token.Token
// Value holds the floating-point number.
Value float64
}
FloatLiteral holds a floating-point number
func (*FloatLiteral) String ¶
func (fl *FloatLiteral) String() string
String returns this object as a string.
func (*FloatLiteral) TokenLiteral ¶
func (fl *FloatLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type ForLoopExpression ¶
type ForLoopExpression struct {
// Token is the actual token
Token token.Token
// Condition is the expression used to determine if the loop
// is still running.
Condition Expression
// Consequence is the set of statements to be executed for the
// loop body.
Consequence *BlockStatement
}
ForLoopExpression holds a for-loop
func (*ForLoopExpression) String ¶
func (fle *ForLoopExpression) String() string
String returns this object as a string.
func (*ForLoopExpression) TokenLiteral ¶
func (fle *ForLoopExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type ForeachStatement ¶
type ForeachStatement struct {
// Token is the actual token
Token token.Token
// Index is the variable we'll set with the index, for the blocks' scope
// This is optional.
Index string
// Ident is the variable we'll set with each item, for the blocks' scope
Ident string
// Value is the thing we'll range over.
Value Expression
// Body is the block we'll execute.
Body *BlockStatement
}
ForeachStatement holds a foreach-statement.
func (*ForeachStatement) String ¶
func (fes *ForeachStatement) String() string
String returns this object as a string.
func (*ForeachStatement) TokenLiteral ¶
func (fes *ForeachStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type FunctionLiteral ¶
type FunctionLiteral struct {
// Token is the actual token
Token token.Token
// Parameters is the list of parameters the function receives.
Parameters []*Identifier
// Defaults holds any default values for arguments which aren't
// specified
Defaults map[string]Expression
// Body contains the set of statements within the function.
Body *BlockStatement
// DocString
DocString *DocStringLiteral
}
FunctionLiteral holds a function-definition
func (*FunctionLiteral) String ¶
func (fl *FunctionLiteral) String() string
String returns this object as a string.
func (*FunctionLiteral) TokenLiteral ¶
func (fl *FunctionLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type HashLiteral ¶
type HashLiteral struct {
// Token holds the token
Token token.Token // the '{' token
// Pairs stores the name/value sets of the hash-content
Pairs map[Expression]Expression
}
HashLiteral holds a hash definition
func (*HashLiteral) String ¶
func (hl *HashLiteral) String() string
String returns this object as a string.
func (*HashLiteral) TokenLiteral ¶
func (hl *HashLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type Identifier ¶
type Identifier struct {
// Token is the literal token
Token token.Token
// Value is the name of the identifier
Value string
}
Identifier holds a single identifier.
func (*Identifier) String ¶
func (i *Identifier) String() string
String returns this object as a string.
func (*Identifier) TokenLiteral ¶
func (i *Identifier) TokenLiteral() string
TokenLiteral returns the literal token.
type IfExpression ¶
type IfExpression struct {
// Token is the actual token
Token token.Token
// Condition is the thing that is evaluated to determine
// which block should be executed.
Condition Expression
// Consequence is the set of statements executed if the
// condition is true.
Consequence *BlockStatement
// Alternative is the set of statements executed if the
// condition is not true (optional).
Alternative *BlockStatement
}
IfExpression holds an if-statement
func (*IfExpression) String ¶
func (ie *IfExpression) String() string
String returns this object as a string.
func (*IfExpression) TokenLiteral ¶
func (ie *IfExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type ImportExpression ¶
type ImportExpression struct {
Token token.Token // The 'import' token
Name Expression
}
ImportExpression represents an `import` expression and holds the name of the module being imported.
func (*ImportExpression) String ¶
func (ie *ImportExpression) String() string
String returns a stringified version of the AST for debugging
func (*ImportExpression) TokenLiteral ¶
func (ie *ImportExpression) TokenLiteral() string
TokenLiteral prints the literal value of the token associated with this node
type IndexExpression ¶
type IndexExpression struct {
// Token is the actual token
Token token.Token
// Left is the thing being indexed.
Left Expression
// Index is the value we're indexing
Index Expression
}
IndexExpression holds an index-expression
func (*IndexExpression) String ¶
func (ie *IndexExpression) String() string
String returns this object as a string.
func (*IndexExpression) TokenLiteral ¶
func (ie *IndexExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type InfixExpression ¶
type InfixExpression struct {
// Token holds the literal expression
Token token.Token
// Left holds the left-most argument
Left Expression
// Operator holds the operation to be carried out (e.g. "+", "-")
Operator string
// Right holds the right-most argument
Right Expression
}
InfixExpression stores an infix expression.
func (*InfixExpression) String ¶
func (ie *InfixExpression) String() string
String returns this object as a string.
func (*InfixExpression) TokenLiteral ¶
func (ie *InfixExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type IntegerLiteral ¶
type IntegerLiteral struct {
// Token is the literal token
Token token.Token
// Value holds the integer.
Value int64
}
IntegerLiteral holds an integer
func (*IntegerLiteral) String ¶
func (il *IntegerLiteral) String() string
String returns this object as a string.
func (*IntegerLiteral) TokenLiteral ¶
func (il *IntegerLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type LetStatement ¶
type LetStatement struct {
// Token is the token
Token token.Token
// Name is the name of the variable we're setting
Name *Identifier
// Value contains the value which is to be set
Value Expression
}
LetStatement is the same as mutable-statement, but the value can't be changed later.
func (*LetStatement) String ¶
func (ls *LetStatement) String() string
String returns this object as a string.
func (*LetStatement) TokenLiteral ¶
func (ls *LetStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type MutableStatement ¶
type MutableStatement struct {
// Token holds the token
Token token.Token
// Name is the name of the variable to which we're assigning
Name *Identifier
// Value is the thing we're storing in the variable.
Value Expression
}
MutableStatement holds a mutable-statemnt
func (*MutableStatement) String ¶
func (ls *MutableStatement) String() string
String returns this object as a string.
func (*MutableStatement) TokenLiteral ¶
func (ls *MutableStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type Node ¶
type Node interface {
// TokenLiteral returns the literal of the token.
TokenLiteral() string
// String returns this object as a string.
String() string
}
Node reresents a node.
type NullLiteral ¶ added in v0.6.0
NullLiteral represents a literal null
func (*NullLiteral) String ¶ added in v0.6.0
func (n *NullLiteral) String() string
String returns this object as a string.
func (*NullLiteral) TokenLiteral ¶ added in v0.6.0
func (n *NullLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
type PostfixExpression ¶
type PostfixExpression struct {
// Token holds the token we're operating upon
Token token.Token
// Operator holds the postfix token, e.g. ++
Operator string
}
PostfixExpression holds a postfix-based expression
func (*PostfixExpression) String ¶
func (pe *PostfixExpression) String() string
String returns this object as a string.
func (*PostfixExpression) TokenLiteral ¶
func (pe *PostfixExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type PrefixExpression ¶
type PrefixExpression struct {
// Token holds the token. e.g. "!"
Token token.Token
// Operator holds the operator being invoked (e.g. "!").
Operator string
// Right holds the thing to be operated upon
Right Expression
}
PrefixExpression holds a prefix-based expression
func (*PrefixExpression) String ¶
func (pe *PrefixExpression) String() string
String returns this object as a string.
func (*PrefixExpression) TokenLiteral ¶
func (pe *PrefixExpression) TokenLiteral() string
TokenLiteral returns the literal token.
type Program ¶
type Program struct {
// Statements is the set of statements which the program is comprised
// of.
Statements []Statement
}
Program represents a complete program.
func (*Program) TokenLiteral ¶
TokenLiteral returns the literal token of our program.
type ReturnStatement ¶
type ReturnStatement struct {
// Token contains the literal token.
Token token.Token
// ReturnValue is the value whichis to be returned.
ReturnValue Expression
}
ReturnStatement stores a return-statement
func (*ReturnStatement) String ¶
func (rs *ReturnStatement) String() string
String returns this object as a string.
func (*ReturnStatement) TokenLiteral ¶
func (rs *ReturnStatement) TokenLiteral() string
TokenLiteral returns the literal token.
type SpreadLiteral ¶ added in v0.8.1
type SpreadLiteral struct {
// Token is ....
Token token.Token
// Right is the value being spread out of
Right Expression
}
SpreadLiteral holds a spread node
func (*SpreadLiteral) String ¶ added in v0.8.1
func (s *SpreadLiteral) String() string
String returns a string representation of the literal
func (*SpreadLiteral) TokenLiteral ¶ added in v0.8.1
func (s *SpreadLiteral) TokenLiteral() string
TokenLiteral returns the spread token
type Statement ¶
type Statement interface {
// Node is the node holding the actual statement
Node
// contains filtered or unexported methods
}
Statement represents a single statement.
type StringLiteral ¶
type StringLiteral struct {
// Token is the token
Token token.Token
// Value is the value of the string.
Value string
}
StringLiteral holds a string
func (*StringLiteral) String ¶
func (sl *StringLiteral) String() string
String returns this object as a string.
func (*StringLiteral) TokenLiteral ¶
func (sl *StringLiteral) TokenLiteral() string
TokenLiteral returns the literal token.
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