some lexer stuff

.vscode/settings.json

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+{
+    "deno.enable": true
+}

deno.jsonc

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+{
+    "fmt": {
+        "indentWidth": 4
+    }
+}

src/Lexer.ts

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+import { Pos, Token } from "./Token.ts";
+
+class Lexer {
+    private index = 0;
+    private line = 1;
+    private col = 1;
+
+
+    public constructor (private text: string) {}
+
+    public next(): Token | null { return null }
+    
+    private done(): boolean { return this.index >= this.text.length; }
+    private current(): string { return this.text[this.index]; }
+
+    private step() {
+        if (this.done())
+            return;
+        if (this.current() === "\n") {
+            this.line += 1;
+            this.col = 1;
+        } else {
+            this.col += 1;
+        }
+        this.index += 1;
+    }
+
+    private pos(): Pos {
+        return {
+            index: this.index,
+            line: this.line,
+            col: this.col
+        }
+    }
+
+    private token(type: string, pos: Pos): Token {
+        const length = this.index - pos.index;
+        return { type, pos, length };
+    }
+}

src/Token.ts

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+export type Token = {
+    type: string;
+    pos: Pos;
+    length: number;
+    identValue?: string;
+    intValue?: number;
+    stringValue?: string;
+};
+
+export type Pos = {
+    index: number;
+    line: number;
+    col: number;
+};