purify std.uni constructs, blocked by std.algortihm.sort

std/uni.d

@@ -1390,7 +1390,6 @@ private struct SliceOverIndexed(T)
 {
     enum assignableIndex = is(typeof((){ T.init[0] = Item.init; }));
     enum assignableSlice = is(typeof((){ T.init[0..0] = Item.init; }));
-
     auto opIndex(size_t idx)const
     in
     {
@@ -1888,6 +1887,7 @@ public alias CodepointSet = InversionList!GcPolicy;
 */
 public struct CodepointInterval
 {
+pure:
     uint[2] _tuple;
     alias _tuple this;
     this(uint low, uint high)
@@ -1899,8 +1899,8 @@ public struct CodepointInterval
     {
         return this[0] == val[0] && this[1] == val[1];
     }
-    @property ref uint a(){ return _tuple[0]; }
+    @property ref inout(uint) a() inout { return _tuple[0]; }
-    @property ref uint b(){ return _tuple[1]; }
+    @property ref inout(uint) b() inout { return _tuple[1]; }
 }
 
 //@@@BUG another forward reference workaround
@@ -1980,10 +1980,11 @@ public struct CodepointInterval
 @trusted public struct InversionList(SP=GcPolicy)
 {
 public:
+
     /**
         Construct from another code point set of any type.
     */
-    this(Set)(Set set)
+    this(Set)(Set set) pure
         if(isCodepointSet!Set)
     {
         uint[] arr;
@@ -1998,7 +1999,7 @@ public:
     /**
         Construct a set from a forward range of code point intervals.
     */
-    this(Range)(Range intervals)
+    this(Range)(Range intervals) /*pure */ //@@@BUG@@@ sort is not pure
         if(isForwardRange!Range && isIntegralPair!(ElementType!Range))
     {
         auto flattened = roundRobin(intervals.save.map!"a[0]"(),
@@ -2008,7 +2009,7 @@ public:
     }
 
     //helper function that avoids sanity check to be CTFE-friendly
-    private static fromIntervals(Range)(Range intervals)
+    private static fromIntervals(Range)(Range intervals) pure
     {
         auto flattened = roundRobin(intervals.save.map!"a[0]"(),
             intervals.save.map!"a[1]"());
@@ -2016,6 +2017,23 @@ public:
         set.data = Uint24Array!(SP)(flattened);
         return set;
     }
+    //ditto untill sort is CTFE-able
+    private static fromIntervals()(uint[] intervals...) pure
+    in
+    {
+        assert(intervals.length % 2 == 0, "Odd number of interval bounds [a, b)!");
+        for(uint i=0; i<intervals.length/2; i++)
+        {
+            auto a = intervals[2*i], b = intervals[2*i+1];
+            assert(a < b, text("illegal interval [a, b): ", a, " > ", b));
+        }
+    }
+    body
+    {
+        InversionList set;
+        set.data = Uint24Array!(SP)(intervals);
+        return set;
+    }
 
     /**
         Construct a set from plain values of code point intervals.
@@ -4790,8 +4808,8 @@ template Utf16Matcher()
     auto build(Set)(Set set)
     {
         auto ascii = set & unicode.ASCII;
-        auto bmp = (set & CodepointSet(0x80, 0xFFFF+1)) 
+        auto bmp = (set & CodepointSet.fromIntervals(0x80, 0xFFFF+1))
-            - CodepointSet(0xD800, 0xDFFF+1);
+            - CodepointSet.fromIntervals(0xD800, 0xDFFF+1);
         auto other = set - (bmp | ascii);
         auto asciiT = ascii.byCodepoint.map!(x=>cast(char)x).buildTrie!(AsciiSpec);
         auto bmpT = bmp.byCodepoint.map!(x=>cast(wchar)x).buildTrie!(BmpSpec);
@@ -4991,7 +5009,7 @@ public auto utfMatcher(Char, Set)(Set set)
 
 
 //a range of code units, packed with index to speed up forward iteration
-public auto decoder(C)(C[] s, size_t offset=0)
+package auto decoder(C)(C[] s, size_t offset=0)
     if(is(C : wchar) || is(C : char))
 {
     static struct Decoder
@@ -5020,7 +5038,7 @@ public auto decoder(C)(C[] s, size_t offset=0)
     Expose UTF string $(D s) as a random-access
     range of $(S_LINK Code unit, code units).
 */
-public auto units(C)(C[] s)
+package auto units(C)(C[] s)
     if(is(C : wchar) || is(C : char))
 {
     static struct Units
@@ -5562,13 +5580,14 @@ unittest
 }
 
 // Creates a range of $(D CodepointInterval) that lazily decodes compressed data.
-@safe package auto decompressIntervals(const(ubyte)[] data)
+@safe package auto decompressIntervals(const(ubyte)[] data) pure
 {
     return DecompressedIntervals(data);
 }
 
 @trusted struct DecompressedIntervals
 {
+pure:
     const(ubyte)[] _stream;
     size_t _idx;
     CodepointInterval _front;
@@ -5620,7 +5639,7 @@ else
 {
 
 // helper for looking up code point sets
-@trusted ptrdiff_t findUnicodeSet(alias table, C)(in C[] name)
+@trusted ptrdiff_t findUnicodeSet(alias table, C)(in C[] name) pure
 {
     auto range = assumeSorted!((a,b) => propertyNameLess(a,b))
         (table.map!"a.name"());
@@ -5631,7 +5650,7 @@ else
 }
 
 // another one that loads it
-@trusted bool loadUnicodeSet(alias table, Set, C)(in C[] name, ref Set dest)
+@trusted bool loadUnicodeSet(alias table, Set, C)(in C[] name, ref Set dest) pure
 {
     auto idx = findUnicodeSet!table(name);
     if(idx >= 0)
@@ -5643,7 +5662,7 @@ else
 }
 
 @trusted bool loadProperty(Set=CodepointSet, C)
-    (in C[] name, ref Set target)
+    (in C[] name, ref Set target) pure
 {
     alias ucmp = comparePropertyName;
     // conjure cumulative properties by hand
@@ -5731,9 +5750,9 @@ else
         target |= asSet(uniProps.So);
     }
     else if(ucmp(name, "any") == 0)
-        target = Set(0,0x110000);
+        target = Set.fromIntervals(0, 0x110000);
     else if(ucmp(name, "ascii") == 0)
-        target = Set(0,0x80);
+        target = Set.fromIntervals(0, 0x80);
     else
         return loadUnicodeSet!(uniProps.tab)(name, target);
     return true;
@@ -5837,7 +5856,7 @@ template SetSearcher(alias table, string kind)
         ---
     */
 
-    static @property auto opDispatch(string name)()
+    static @property auto opDispatch(string name)() pure
     {
         static if(findAny(name))
             return loadAny(name);
@@ -5943,7 +5962,7 @@ private:
             || (ucmp(name[0..2],"In") == 0 && findSetName!(blocks.tab)(name[2..$]));
     }
 
-    static auto loadAny(Set=CodepointSet, C)(in C[] name)
+    static auto loadAny(Set=CodepointSet, C)(in C[] name) pure
     {
         Set set;
         bool loaded = loadProperty(name, set) || loadUnicodeSet!(scripts.tab)(name, set)
@@ -8586,7 +8605,7 @@ private:
 // load static data from pre-generated tables into usable datastructures
 
 
-@safe auto asSet(const (ubyte)[] compressed)
+@safe auto asSet(const (ubyte)[] compressed) pure
 {
     return CodepointSet.fromIntervals(decompressIntervals(compressed));
 }