72 lines
1 KiB
Go
72 lines
1 KiB
Go
package main
|
|
|
|
import (
|
|
"bufio"
|
|
"log"
|
|
"os"
|
|
)
|
|
|
|
func main() {
|
|
expr := &Binary{
|
|
&Unary{Token{MINUS, "-", nil, 1}, &Literal{123}},
|
|
Token{STAR, "*", nil, 1},
|
|
&Grouping{&Grouping{&Binary{
|
|
&Unary{Token{MINUS, "-", nil, 1}, &Literal{123}},
|
|
Token{STAR, "*", nil, 1},
|
|
&Grouping{&Grouping{&Literal{45.67}}}}}},
|
|
}
|
|
|
|
println(AstStringer{}.String(expr))
|
|
|
|
switch len(os.Args) {
|
|
case 1:
|
|
runPrompt()
|
|
case 2:
|
|
runFile(os.Args[1])
|
|
default:
|
|
println("Usage: glox [file]")
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
|
|
func runPrompt() {
|
|
scanner := bufio.NewScanner(os.Stdin)
|
|
scanner.Split(bufio.ScanLines)
|
|
|
|
for {
|
|
print("> ")
|
|
scanner.Scan()
|
|
line := scanner.Text()
|
|
if len(line) == 0 {
|
|
break
|
|
}
|
|
run([]byte(scanner.Text()))
|
|
hadError = false
|
|
}
|
|
}
|
|
|
|
func runFile(path string) {
|
|
file, err := os.ReadFile(path)
|
|
|
|
panic(err)
|
|
|
|
run(file)
|
|
|
|
if hadError {
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
|
|
func run(source []byte) {
|
|
tokens := newScanner(source).scan()
|
|
|
|
for _, token := range tokens {
|
|
println(token.String())
|
|
}
|
|
}
|
|
|
|
func panic(err error) {
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|