Pure Python Go parser, AST and unparser library
$ pip3 install gopygoParse and unparse the Go Hello, World! example:
>>> import gopygo
>>> program = """
... package main
...
... import "fmt"
...
... func main() {
... fmt.Println("Hello, World!")
... }
... """
>>> program = program.lstrip()
>>> tree = gopygo.parse(program)
>>> tree
<gopygo.ast.File object at 0x7f0b5dddb6d0>
>>> tree.__dict__
{'name': <gopygo.ast.Package object at 0x7f0b5dddb0a0>, 'imports': [<gopygo.ast.ImportSpec object at 0x7f0b5dddb190>], 'decls': [<gopygo.ast.FuncDecl object at 0x7f0b5dddb520>]}
>>> text = gopygo.unparse(tree)
>>> print(text)
package main
import "fmt"
func main() {
fmt.Println("Hello, World!")
}
>>> assert program == textImplement the AST nodes specified in here and the parser, unparser libraries accordingly.
Tokens are defined in here.
Here is an example access Go AST using original go/parser and go/ast packages:
package main
import "fmt"
import "go/token"
import "go/parser"
import "go/ast"
func main() {
src := `
package main
import "fmt"
func main() {
fmt.Println("Hello, World!")
}
`
x, err := parser.ParseFile(token.NewFileSet(), "", src, 0)
fmt.Println(x.Decls[1].(*ast.FuncDecl).Body.List[0].(*ast.ExprStmt).X.(*ast.CallExpr).Args[0].(*ast.BasicLit).Value)
fmt.Println(err)
fmt.Printf("type: %T\n", x.Decls[1].(*ast.FuncDecl).Body.List[0].(*ast.ExprStmt).X.(*ast.CallExpr).Args[0].(*ast.BasicLit).Value)
}Gives this output:
"Hello, World!"
<nil>
type: string