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CLI Tokenizer - feels like bash
function tokenize (input) {
function Token(type, isOpenUntil) {
this.type = type;
this.value = "";
this.isOpenUntil = isOpenUntil || false;
}
var i = 0,
len = input.length,
tokens = [],
currentToken = new Token("EMPTY"),
currentChar;
function next (type, isOpenUntil) {
tokens.push(currentToken);
currentToken = new Token(type, isOpenUntil);
}
while (i < len) {
currentChar = input.charAt(i);
if (currentToken.isOpenUntil) {
if (currentChar == currentToken.isOpenUntil)
currentToken.isOpenUntil = false;
else
currentToken.value += currentChar;
} else {
if (currentChar == "\\") {
if (currentToken.type != "WORD") next("WORD");
i++;
currentToken.value += input.charAt(i);
} else if (currentChar == "&") {
if (currentToken.type == "AMP") currentToken.type = "AND";
else next("AMP");
} else if (currentChar == "|") {
if (currentToken.type == "PIPE") currentToken.type = "OR";
else next("PIPE");
} else if (currentChar == ">") next("OUT");
else if (currentChar == "<") next("IN");
else if (currentChar == ";") next("SEMICOLON");
else if (currentChar == "\"") next("STRING", "\"");
else if (currentChar == "'") next("STRING", "'");
else if (currentChar == "(") next("SUBOPEN");
else if (currentChar == ")") next("SUBCLOSE");
else {
if (currentToken.type == "WORD")
currentToken.value += currentChar;
else {
next("WORD");
currentToken.value = currentChar;
}
}
}
i++;
}
tokens.push(currentToken); // append current token
tokens.shift(); // remove empty token
return tokens;
}
var input = '(true||false)&& echo foo bar \\> > baz | world; echo "bla bla" && \'foo\'';
require("console").log(tokenize(input));
/* result:
[ { type: 'SUBOPEN', value: '', isOpenUntil: false },
{ type: 'WORD', value: 'true', isOpenUntil: false },
{ type: 'OR', value: '', isOpenUntil: false },
{ type: 'WORD', value: 'false', isOpenUntil: false },
{ type: 'SUBCLOSE', value: '', isOpenUntil: false },
{ type: 'AND', value: '', isOpenUntil: false },
{ type: 'WORD', value: ' echo foo bar > ', isOpenUntil: false },
{ type: 'OUT', value: '', isOpenUntil: false },
{ type: 'WORD', value: ' baz ', isOpenUntil: false },
{ type: 'PIPE', value: '', isOpenUntil: false },
{ type: 'WORD', value: ' world', isOpenUntil: false },
{ type: 'SEMICOLON', value: '', isOpenUntil: false },
{ type: 'WORD', value: ' echo ', isOpenUntil: false },
{ type: 'STRING', value: 'bla bla', isOpenUntil: false },
{ type: 'WORD', value: ' ', isOpenUntil: false },
{ type: 'AND', value: '', isOpenUntil: false },
{ type: 'WORD', value: ' ', isOpenUntil: false },
{ type: 'STRING', value: 'foo', isOpenUntil: false } ]*/
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