diff --git a/spec.html b/spec.html index 58f581d09f..cb853e8df1 100644 --- a/spec.html +++ b/spec.html @@ -9342,6 +9342,26 @@

Static Semantics: UTF16Decode ( _lead_, _trail_ )

1. Return the code point _cp_. + + +

Static Semantics: CodePointAt ( _string_, _position_ )

+

The abstract operation CodePointAt interprets a String _string_ as a sequence of UTF-16 encoded code points, as described in , and reads from it a single code point starting with the code unit at index _position_. When called, the following steps are performed:

+ + 1. Let _size_ be the length of _string_. + 1. Assert: _position_ ≥ 0 and _position_ < _size_. + 1. Let _first_ be the code unit at index _position_ within _string_. + 1. Let _cp_ be the code point whose numeric value is that of _first_. + 1. If _first_ is not a or , then + 1. Return a new Record { [[CodePoint]]: _cp_, [[CodeUnitCount]]: 1, [[IsUnpairedSurrogate]]: *false* }. + 1. If _first_ is a or _position_ + 1 = _size_, then + 1. Return a new Record { [[CodePoint]]: _cp_, [[CodeUnitCount]]: 1, [[IsUnpairedSurrogate]]: *true* }. + 1. Let _second_ be the code unit at index _position_ + 1 within _string_. + 1. If _second_ is not a , then + 1. Return a new Record { [[CodePoint]]: _cp_, [[CodeUnitCount]]: 1, [[IsUnpairedSurrogate]]: *true* }. + 1. Set _cp_ to ! UTF16Decode(_first_, _second_). + 1. Return a new Record { [[CodePoint]]: _cp_, [[CodeUnitCount]]: 2, [[IsUnpairedSurrogate]]: *false* }. + + @@ -23706,25 +23726,18 @@

Runtime Semantics: Encode ( _string_, _unescapedSet_ )

1. If _k_ equals _strLen_, return _R_. 1. Let _C_ be the code unit at index _k_ within _string_. 1. If _C_ is in _unescapedSet_, then - 1. Let _S_ be the String value containing only the code unit _C_. - 1. Set _R_ to the string-concatenation of the previous value of _R_ and _S_. + 1. Set _k_ to _k_ + 1. + 1. Set _R_ to the string-concatenation of the previous value of _R_ and _C_. 1. Else, - 1. If _C_ is a , throw a *URIError* exception. - 1. If _C_ is not a , then - 1. Let _V_ be the code point with the same numeric value as code unit _C_. - 1. Else, - 1. Increase _k_ by 1. - 1. If _k_ equals _strLen_, throw a *URIError* exception. - 1. Let _kChar_ be the code unit at index _k_ within _string_. - 1. If _kChar_ is not a , throw a *URIError* exception. - 1. Let _V_ be UTF16Decode(_C_, _kChar_). - 1. Let _Octets_ be the List of octets resulting by applying the UTF-8 transformation to _V_. + 1. Let _cp_ be ! CodePointAt(_string_, _k_). + 1. If _cp_.[[IsUnpairedSurrogate]] is *true*, throw a *URIError* exception. + 1. Set _k_ to _k_ + _cp_.[[CodeUnitCount]]. + 1. Let _Octets_ be the List of octets resulting by applying the UTF-8 transformation to _cp_.[[CodePoint]]. 1. For each element _octet_ of _Octets_ in List order, do - 1. Let _S_ be the string-concatenation of: + 1. Set _R_ to the string-concatenation of: + * the previous value of _R_ * `"%"` * the String representation of _octet_, formatted as a two-digit uppercase hexadecimal number, padded to the left with a zero if necessary - 1. Set _R_ to the string-concatenation of the previous value of _R_ and _S_. - 1. Increase _k_ by 1. @@ -28300,7 +28313,7 @@

String.prototype.charCodeAt ( _pos_ )

String.prototype.codePointAt ( _pos_ )

-

Returns a nonnegative integer Number less than 0x110000 that is the code point value of the UTF-16 encoded code point () starting at the string element at index _pos_ within the String resulting from converting this object to a String. If there is no element at that index, the result is *undefined*. If a valid UTF-16 does not begin at _pos_, the result is the code unit at _pos_.

+

Returns a nonnegative integer Number less than or equal to 0x10FFFF that is the code point value of the UTF-16 encoded code point () starting at the string element at index _pos_ within the String resulting from converting this object to a String. If there is no element at that index, the result is *undefined*. If a valid UTF-16 does not begin at _pos_, the result is the code unit at _pos_.

When the `codePointAt` method is called with one argument _pos_, the following steps are taken:

@@ -28309,11 +28322,8 @@

String.prototype.codePointAt ( _pos_ )

1. Let _position_ be ? ToInteger(_pos_). 1. Let _size_ be the length of _S_. 1. If _position_ < 0 or _position_ ≥ _size_, return *undefined*. - 1. Let _first_ be the numeric value of the code unit at index _position_ within the String _S_. - 1. If _first_ < 0xD800 or _first_ > 0xDBFF or _position_ + 1 = _size_, return _first_. - 1. Let _second_ be the numeric value of the code unit at index _position_ + 1 within the String _S_. - 1. If _second_ < 0xDC00 or _second_ > 0xDFFF, return _first_. - 1. Return UTF16Decode(_first_, _second_). + 1. Let _cp_ be ! CodePointAt(_S_, _position_). + 1. Return _cp_.[[CodePoint]].

The `codePointAt` function is intentionally generic; it does not require that its *this* value be a String object. Therefore it can be transferred to other kinds of objects for use as a method.

@@ -29112,14 +29122,9 @@

%StringIteratorPrototype%.next ( )

1. If _position_ ≥ _len_, then 1. Set _O_.[[IteratedString]] to *undefined*. 1. Return CreateIterResultObject(*undefined*, *true*). - 1. Let _first_ be the numeric value of the code unit at index _position_ within _s_. - 1. If _first_ < 0xD800 or _first_ > 0xDBFF or _position_ + 1 = _len_, let _resultString_ be the String value consisting of the single code unit _first_. - 1. Else, - 1. Let _second_ be the numeric value of the code unit at index _position_ + 1 within the String _s_. - 1. If _second_ < 0xDC00 or _second_ > 0xDFFF, let _resultString_ be the String value consisting of the single code unit _first_. - 1. Else, let _resultString_ be the string-concatenation of the code unit _first_ and the code unit _second_. - 1. Let _resultSize_ be the number of code units in _resultString_. - 1. Set _O_.[[StringIteratorNextIndex]] to _position_ + _resultSize_. + 1. Let _cp_ be ! CodePointAt(_s_, _position_). + 1. Let _resultString_ be the String value containing _cp_.[[CodeUnitCount]] consecutive code units from _s_ beginning with the code unit at index _position_. + 1. Set _O_.[[StringIteratorNextIndex]] to _position_ + _cp_.[[CodeUnitCount]]. 1. Return CreateIterResultObject(_resultString_, *false*). @@ -31015,11 +31020,8 @@

AdvanceStringIndex ( _S_, _index_, _unicode_ )

1. If _unicode_ is *false*, return _index_ + 1. 1. Let _length_ be the number of code units in _S_. 1. If _index_ + 1 ≥ _length_, return _index_ + 1. - 1. Let _first_ be the numeric value of the code unit at index _index_ within _S_. - 1. If _first_ < 0xD800 or _first_ > 0xDBFF, return _index_ + 1. - 1. Let _second_ be the numeric value of the code unit at index _index_ + 1 within _S_. - 1. If _second_ < 0xDC00 or _second_ > 0xDFFF, return _index_ + 1. - 1. Return _index_ + 2. + 1. Let _cp_ be ! CodePointAt(_S_, _index_). + 1. Return _index_ + _cp_.[[CodeUnitCount]].