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SyntaxError: "0"-prefixed octal literals and octal escape seq. are deprecated - JavaScript | MDN
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SyntaxError: "0"-prefixed octal literals and octal escape seq. are deprecated

SyntaxError:
"0"-prefixed octal literals and octal escape sequences are deprecated;
for octal literals use the \"0o\" prefix instead

strict SyntaxError

8 8 strict SyntaxError ECMAScript 2015 0 "O" (0o or 0O)

"0" 8

js
"use strict";

03;

// SyntaxError: "0"-prefixed octal literals and octal escape sequences
// are deprecated

8

js
"use strict";

"\251";

// SyntaxError: "0"-prefixed octal literals and octal escape sequences
// are deprecated

8

0 "o" "O" :

js
0o3;

8 16 :

js
"\xA9";

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