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import std/unicode
# Lookup tables for characters on the BMP. This "only" takes up 8k of space
# per table, as opposed to the 135k that storing all characters would require.
# The downside is obviously that we need a binary search fallback for non-bmp.
# We do not store a lookup table of ambiguous ranges, either.
type
ptint* = int32
PropertyTable* = array[0x10000 div (sizeof(ptint) * 8), ptint]
RangeMap* = openArray[(uint32, uint32)]
func makePropertyTable*(ranges: RangeMap, skip: RangeMap = @[]): PropertyTable =
var ucs: uint32 = 0
var j = 0
var k = 0
while ucs <= 0xFFFF:
if k > ranges.len:
break
if ranges[k][0] > ucs:
ucs = ranges[k][0]
continue
if ranges[k][1] < ucs:
inc k
continue
if j != skip.len and ucs == skip[j][0]:
ucs = skip[j][1] + 1
continue
let i = ucs div (sizeof(ptint) * 8)
let m = ucs mod (sizeof(ptint) * 8)
result[i] = result[i] or ptint(1 shl m)
inc ucs
{.push boundChecks:off.}
func contains*(props: PropertyTable, r: Rune): bool =
let u = ptint(r)
let i = u div (sizeof(ptint) * 8)
let m = u mod (sizeof(ptint) * 8)
return (props[i] and (1 shl m)) != 0
{.pop.}
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