50 lines
1.1 KiB
TypeScript
50 lines
1.1 KiB
TypeScript
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import type { Token } from "./lexer.ts";
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export function scan_string(input: string, starting_position: number): [Token, number] {
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let value = "\"";
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let pos = starting_position + 1;
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while (pos < input.length) {
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const c = input[pos];
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if (c === "\"") {
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value += c;
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pos += 1;
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break;
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}
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if (c === "\n") {
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// todo: error handling, return an error indicator and the caller should render a red wavy underline
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break;
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}
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if (c === "\\") {
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const next_char = input[pos + 1];
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value += handle_escape_char(next_char);
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pos += 2;
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continue;
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}
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value += c;
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pos += 1;
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}
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return [{ v: value, token_type: "string" }, pos];
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}
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function handle_escape_char(next_char: string): string {
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switch (next_char) {
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case "n":
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return "\\n"
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case "t":
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return "\\t"
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case "r":
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return "\\r"
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case "\"":
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return "\\\""
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case "\\":
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return "\\\\"
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default:
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return "\\" + next_char
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}
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}
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