tijani
fdf6a8a552
- Parser can now handle return statements. git-svn-id: https://svn.tlawal.org/svn/monkey@21 f6afcba9-9ef1-4bdd-9b72-7484f5705bac
64 lines
1.0 KiB
Go
64 lines
1.0 KiB
Go
package ast
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import "monkey/token"
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type Node interface {
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TokenLiteral() string
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}
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type Statement interface {
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Node
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statement_node()
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}
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type Expression interface {
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Node
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expression_node()
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}
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type Program struct {
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Statements []Statement
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}
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type Identifier struct {
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Token token.Token // the token.IDENT token
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Value string
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}
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type LetStatement struct {
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Token token.Token // token.LET token
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Name *Identifier
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Value Expression
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}
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type ReturnStatement struct {
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Token token.Token // token.RETURN token
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ReturnValue Expression
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}
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func (ls *LetStatement) statement_node() {}
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func (ls *LetStatement) TokenLiteral() string {
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return ls.Token.Literal
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}
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func (i *Identifier) expression_node() {}
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func (i *Identifier) TokenLiteral() string {
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return i.Token.Literal
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}
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func (p *Program) TokenLiteral() string {
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if len(p.Statements) > 0 {
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return p.Statements[0].TokenLiteral()
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} else {
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return ""
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}
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}
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func (rs *ReturnStatement) statement_node() {}
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func (rs *ReturnStatement) TokenLiteral() string {
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return rs.Token.Literal
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}
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