Editorial: Change If X is not undefined (#472)

Reduce double negative in the spec.

Change from

If X is not undefined then A else B

to

If X is undefined then B else A

spec/datetimeformat.html

@@ -105,13 +105,13 @@ <h1>InitializeDateTimeFormat ( _dateTimeFormat_, _locales_, _options_ )</h1>
         1. Set _dateTimeFormat_.[[NumberingSystem]] to _r_.[[nu]].
         1. Let _dataLocale_ be _r_.[[dataLocale]].
         1. Let _timeZone_ be ? Get(_options_, *"timeZone"*).
-        1. If _timeZone_ is not *undefined*, then
+        1. If _timeZone_ is *undefined*, then
+          1. Let _timeZone_ be DefaultTimeZone().
+        1. Else,
           1. Let _timeZone_ be ? ToString(_timeZone_).
           1. If the result of IsValidTimeZoneName(_timeZone_) is *false*, then
             1. Throw a *RangeError* exception.
           1. Let _timeZone_ be CanonicalizeTimeZoneName(_timeZone_).
-        1. Else,
-          1. Let _timeZone_ be DefaultTimeZone().
         1. Set _dateTimeFormat_.[[TimeZone]] to _timeZone_.
         1. Let _opt_ be a new Record.
         1. For each row of <emu-xref href="#table-datetimeformat-components"></emu-xref>, except the header row, in table order, do
@@ -130,7 +130,10 @@ <h1>InitializeDateTimeFormat ( _dateTimeFormat_, _locales_, _options_ )</h1>
           1. Let _p_ be _bestFormat_.[[&lt;_prop_&gt;]].
           1. If _p_ not *undefined*, then
             1. Set _dateTimeFormat_'s internal slot whose name is the Internal Slot column of the row to _p_.
-        1. If _dateTimeFormat_.[[Hour]] is not *undefined*, then
+        1. If _dateTimeFormat_.[[Hour]] is *undefined*, then
+          1. Set _dateTimeFormat_.[[HourCycle]] to *undefined*.
+          1. Let _pattern_ be _bestFormat_.[[pattern]].
+        1. Else,
           1. Let _hcDefault_ be _dataLocaleData_.[[hourCycle]].
           1. Let _hc_ be _dateTimeFormat_.[[HourCycle]].
           1. If _hc_ is *null*, then
@@ -152,9 +155,6 @@ <h1>InitializeDateTimeFormat ( _dateTimeFormat_, _locales_, _options_ )</h1>
             1. Let _pattern_ be _bestFormat_.[[pattern12]].
           1. Else,
             1. Let _pattern_ be _bestFormat_.[[pattern]].
-        1. Else,
-          1. Set _dateTimeFormat_.[[HourCycle]] to *undefined*.
-          1. Let _pattern_ be _bestFormat_.[[pattern]].
         1. Set _dateTimeFormat_.[[Pattern]] to _pattern_.
         1. Return _dateTimeFormat_.
       </emu-alg>

spec/negotiation.html

@@ -291,10 +291,11 @@ <h1>SupportedLocales ( _availableLocales_, _requestedLocales_, _options_ )</h1>
       </p>
 
       <emu-alg>
-        1. If _options_ is not *undefined*, then
+        1. If _options_ is *undefined*, then
+          1. Let _matcher_ be *"best fit"*.
+        1. Else,
           1. Let _options_ be ? ToObject(_options_).
           1. Let _matcher_ be ? GetOption(_options_, *"localeMatcher"*, *"string"*, &laquo; *"lookup"*, *"best fit"* &raquo;, *"best fit"*).
-        1. Else, let _matcher_ be *"best fit"*.
         1. If _matcher_ is *"best fit"*, then
           1. Let _supportedLocales_ be BestFitSupportedLocales(_availableLocales_, _requestedLocales_).
         1. Else,
@@ -313,16 +314,14 @@ <h1>GetOption ( _options_, _property_, _type_, _values_, _fallback_ )</h1>
       <emu-alg>
         1. Assert: Type(_options_) is Object.
         1. Let _value_ be ? Get(_options_, _property_).
-        1. If _value_ is not *undefined*, then
-          1. Assert: _type_ is *"boolean"* or *"string"*.
-          1. If _type_ is *"boolean"*, then
-            1. Let _value_ be ToBoolean(_value_).
-          1. If _type_ is *"string"*, then
-            1. Let _value_ be ? ToString(_value_).
-          1. If _values_ is not *undefined*, then
-            1. If _values_ does not contain an element equal to _value_, throw a *RangeError* exception.
-          1. Return _value_.
-        1. Else, return _fallback_.
+        1. If _value_ is *undefined*, return _fallback_.
+        1. Assert: _type_ is *"boolean"* or *"string"*.
+        1. If _type_ is *"boolean"*, then
+          1. Let _value_ be ToBoolean(_value_).
+        1. If _type_ is *"string"*, then
+          1. Let _value_ be ? ToString(_value_).
+        1. If _values_ is not *undefined* and _values_ does not contain an element equal to _value_, throw a *RangeError* exception.
+        1. Return _value_.
       </emu-alg>
     </emu-clause>
 
@@ -334,11 +333,10 @@ <h1>DefaultNumberOption ( _value_, _minimum_, _maximum_, _fallback_ )</h1>
       </p>
 
       <emu-alg>
-        1. If _value_ is not *undefined*, then
-          1. Let _value_ be ? ToNumber(_value_).
-          1. If _value_ is *NaN* or less than _minimum_ or greater than _maximum_, throw a *RangeError* exception.
-          1. Return floor(_value_).
-        1. Else, return _fallback_.
+        1. If _value_ is *undefined*, return _fallback_.
+        1. Let _value_ be ? ToNumber(_value_).
+        1. If _value_ is *NaN* or less than _minimum_ or greater than _maximum_, throw a *RangeError* exception.
+        1. Return floor(_value_).
       </emu-alg>
     </emu-clause>
 

spec/numberformat.html

@@ -728,15 +728,17 @@ <h1>SetNumberFormatUnitOptions ( _intlObj_, _options_ )</h1>
         1. Let _style_ be ? GetOption(_options_, *"style"*, *"string"*, &laquo; *"decimal"*, *"percent"*, *"currency"*, *"unit"* &raquo;, *"decimal"*).
         1. Set _intlObj_.[[Style]] to _style_.
         1. Let _currency_ be ? GetOption(_options_, *"currency"*, *"string"*, *undefined*, *undefined*).
-        1. If _currency_ is not *undefined*, then
+        1. If _currency_ is *undefined*, then
+          1. If _style_ is *"currency"*, throw a *TypeError* exception.
+        1. Else, 
           1. If the result of IsWellFormedCurrencyCode(_currency_) is *false*, throw a *RangeError* exception.
-        1. If _style_ is *"currency"* and _currency_ is *undefined*, throw a *TypeError* exception.
         1. Let _currencyDisplay_ be ? GetOption(_options_, *"currencyDisplay"*, *"string"*, &laquo; *"code"*, *"symbol"*, *"narrowSymbol"*, *"name"* &raquo;, *"symbol"*).
         1. Let _currencySign_ be ? GetOption(_options_, *"currencySign"*, *"string"*, &laquo; *"standard"*, *"accounting"* &raquo;, *"standard"*).
         1. Let _unit_ be ? GetOption(_options_, *"unit"*, *"string"*, *undefined*, *undefined*).
-        1. If _unit_ is not *undefined*, then
+        1. If _unit_ is *undefined*, then
+          1. If _style_ is *"unit"*, throw a *TypeError* exception.
+        1. Else,
           1. If the result of IsWellFormedUnitIdentifier(_unit_) is *false*, throw a *RangeError* exception.
-        1. If _style_ is *"unit"* and _unit_ is *undefined*, throw a *TypeError* exception.
         1. Let _unitDisplay_ be ? GetOption(_options_, *"unitDisplay"*, *"string"*, &laquo; *"short"*, *"narrow"*, *"long"* &raquo;, *"short"*).
         1. If _style_ is *"currency"*, then
           1. Let _currency_ be the result of converting _currency_ to upper case as specified in <emu-xref href="#sec-case-sensitivity-and-case-mapping"></emu-xref>.