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@fishmacs
Created March 24, 2012 09:10
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js/sprintf
function str_repeat(i, m) {
for (var o = []; m > 0; o[--m] = i);
return o.join('');
}
function sprintf() {
var i = 0, a, f = arguments[i++], o = [], m, p, c, x, s = '';
while (f) {
if (m = /^[^\x25]+/.exec(f)) {
o.push(m[0]);
}
else if (m = /^\x25{2}/.exec(f)) {
o.push('%');
}
else if (m = /^\x25(?:(\d+)\$)?(\+)?(0|'[^$])?(-)?(\d+)?(?:\.(\d+))?([b-fosuxX])/.exec(f)) {
if (((a = arguments[m[1] || i++]) == null) || (a == undefined)) {
throw('Too few arguments.');
}
if (/[^s]/.test(m[7]) && (typeof(a) != 'number')) {
throw('Expecting number but found ' + typeof(a));
}
switch (m[7]) {
case 'b': a = a.toString(2); break;
case 'c': a = String.fromCharCode(a); break;
case 'd': a = parseInt(a); break;
case 'e': a = m[6] ? a.toExponential(m[6]) : a.toExponential(); break;
case 'f': a = m[6] ? parseFloat(a).toFixed(m[6]) : parseFloat(a); break;
case 'o': a = a.toString(8); break;
case 's': a = ((a = String(a)) && m[6] ? a.substring(0, m[6]) : a); break;
case 'u': a = Math.abs(a); break;
case 'x': a = a.toString(16); break;
case 'X': a = a.toString(16).toUpperCase(); break;
}
a = (/[def]/.test(m[7]) && m[2] && a >= 0 ? '+'+ a : a);
c = m[3] ? m[3] == '0' ? '0' : m[3].charAt(1) : ' ';
x = m[5] - String(a).length - s.length;
p = m[5] ? str_repeat(c, x) : '';
o.push(s + (m[4] ? a + p : p + a));
}
else {
throw('Huh ?!');
}
f = f.substring(m[0].length);
}
return o.join('');
}
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