trimStart() method removes whitespace from the beginning of a string and returns a new string, without modifying the original string.
trimLeft() is an alias of this method.
A new string representing
str stripped of whitespace from its beginning (left side). Whitespace is defined as white space characters plus line terminators.
If the beginning of
str has no whitespace, a new string is still returned (essentially a copy of
trim() was standardized, engines also implemented the non-standard method
trimLeft. However, for consistency with
padEnd(), when the method got standardized, its name was chosen as
trimStart. For web compatibility reasons,
trimLeft remains as an alias to
trimStart, and they refer to the exact same function object. In some engines this means:
String.prototype.trimLeft.name === "trimStart";
The following example trims whitespace from the start of
str, but not from its end.
let str = " foo "; console.log(str.length); // 8 str = str.trimStart(); console.log(str.length); // 5 console.log(str); // 'foo '
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