umx_compiler

commit b2cb2a1c4d76faa74a9a398f498bc0d866628f0b
parent 5b743e7aeec89865a7c1723048b9bddb79b9f07b
Author: bsandro <email@bsandro.tech>
Date:   Sat, 11 Jun 2022 23:31:28 +0300

Lexer demo - interactive demo binary

Diffstat:
A
.gitignore
 | 
1
+
A
main.go
 | 
17
+++++++++++++++++
A
repl/repl.go
 | 
30
++++++++++++++++++++++++++++++

3 files changed, 48 insertions(+), 0 deletions(-)
diff --git a/.gitignore b/.gitignore
@@ -0,0 +1 @@
+interp
diff --git a/main.go b/main.go
@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/user"
+	"interp/repl"
+)
+
+func main() {
+	user, err := user.Current()
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("ehlo %s, this is a potato interpretator cleverly named 'interp'\n", user.Username)
+	repl.Start(os.Stdin, os.Stdout)
+}
diff --git a/repl/repl.go b/repl/repl.go
@@ -0,0 +1,30 @@
+package repl
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"interp/lexer"
+	"interp/token"
+)
+
+const PROMPT = "$> "
+
+func Start(in io.Reader, out io.Writer) {
+	scanner := bufio.NewScanner(in)
+
+	for {
+		fmt.Fprintf(out, PROMPT)
+		scanned := scanner.Scan()
+		if !scanned {
+			return
+		}
+
+		line := scanner.Text()
+		l := lexer.New(line)
+
+		for tok := l.NextToken(); tok.Type != token.EOF; tok = l.NextToken() {
+			fmt.Fprintf(out, "%+v\n", tok)
+		}
+	}
+}