// flags : parser flags
private Frag rune(int[] runes, int flags)
{
Frag f = newInst(Inst.InstOp.RUNE);
Inst i = prog.getInst(f.i);
i.runes = runes;
flags &= RE2.FOLD_CASE; // only relevant flag is FoldCase
if (runes.Length != 1 || Unicode.simpleFold(runes[0]) == runes[0])
{
flags &= ~RE2.FOLD_CASE; // and sometimes not even that
}
i.arg = flags;
f.@out = f.i << 1;
// Special cases for exec machine.
if (((flags & RE2.FOLD_CASE) == 0 && runes.Length == 1) ||
(runes.Length == 2 && runes[0] == runes[1]))
{
i.op = Inst.InstOp.RUNE1;
}
else if (runes.Length == 2 && runes[0] == 0 && runes[1] == Unicode.MAX_RUNE)
{
i.op = Inst.InstOp.RUNE_ANY;
}
else if (runes.Length == 4 &&
runes[0] == 0 &&
runes[1] == '\n' - 1 &&
runes[2] == '\n' + 1 &&
runes[3] == Unicode.MAX_RUNE)
{
i.op = Inst.InstOp.RUNE_ANY_NOT_NL;
}
return(f);
}
// appendFoldedRange() appends the range [lo-hi] and its case
// folding-equivalent runes to this CharClass.
public CharClass appendFoldedRange(int lo, int hi)
{
// Optimizations.
if (lo <= Unicode.MIN_FOLD && hi >= Unicode.MAX_FOLD)
{
// Range is full: folding can't add more.
return(appendRange(lo, hi));
}
if (hi < Unicode.MIN_FOLD || lo > Unicode.MAX_FOLD)
{
// Range is outside folding possibilities.
return(appendRange(lo, hi));
}
if (lo < Unicode.MIN_FOLD)
{
// [lo, minFold-1] needs no folding.
appendRange(lo, Unicode.MIN_FOLD - 1);
lo = Unicode.MIN_FOLD;
}
if (hi > Unicode.MAX_FOLD)
{
// [maxFold+1, hi] needs no folding.
appendRange(Unicode.MAX_FOLD + 1, hi);
hi = Unicode.MAX_FOLD;
}
// Brute force. Depend on appendRange to coalesce ranges on the fly.
for (int c = lo; c <= hi; c++)
{
appendRange(c, c);
for (int f = Unicode.simpleFold(c); f != c; f = Unicode.simpleFold(f))
{
appendRange(f, f);
}
}
return(this);
}
// Appends a RE2 literal to |out| for rune |rune|,
// with regexp metacharacters escaped.
public static void escapeRune(StringBuilder @out, int rune)
{
if (Unicode.isPrint(rune))
{
if (METACHARACTERS.IndexOf((char)rune) >= 0)
{
@out.Append('\\');
}
// Extremely painful Dot NET!
// Convert UTF-32 character to a UTF-16 String.
var strC = Char.ConvertFromUtf32(rune);
@out.Append(strC);
return;
}
switch (rune)
{
case '"':
@out.Append("\\\"");
break;
case '\\':
@out.Append("\\\\");
break;
case '\t':
@out.Append("\\t");
break;
case '\n':
@out.Append("\\n");
break;
case '\r':
@out.Append("\\r");
break;
case '\b':
@out.Append("\\b");
break;
case '\f':
@out.Append("\\f");
break;
default:
{
String s = rune.ToString("X");
if (rune < 0x100)
{
@out.Append("\\x");
if (s.Length == 1)
{
@out.Append('0');
}
@out.Append(s);
}
else
{
@out.Append("\\x{").Append(s).Append('}');
}
break;
}
}
}
// MatchRune returns true if the instruction matches (and consumes) r.
// It should only be called when op == InstRune.
public bool matchRune(int r)
{
// Special case: single-rune slice is from literal string, not char
// class.
if (runes.Length == 1)
{
int r0 = runes[0];
if (r == r0)
{
return(true);
}
if ((arg & RE2.FOLD_CASE) != 0)
{
for (int r1 = Unicode.simpleFold(r0); r1 != r0; r1 = Unicode.simpleFold(r1))
{
if (r == r1)
{
return(true);
}
}
}
return(false);
}
// Peek at the first few pairs.
// Should handle ASCII well.
for (int j = 0; j < runes.Length && j <= 8; j += 2)
{
if (r < runes[j])
{
return(false);
}
if (r <= runes[j + 1])
{
return(true);
}
}
// Otherwise binary search.
for (int lo = 0, hi = runes.Length / 2; lo < hi;)
{
int m = lo + (hi - lo) / 2;
int c = runes[2 * m];
if (c <= r)
{
if (r <= runes[2 * m + 1])
{
return(true);
}
lo = m + 1;
}
else
{
hi = m;
}
}
return(false);
}
