diff options
Diffstat (limited to 'compiler/strutils2.nim')
-rw-r--r-- | compiler/strutils2.nim | 57 |
1 files changed, 0 insertions, 57 deletions
diff --git a/compiler/strutils2.nim b/compiler/strutils2.nim deleted file mode 100644 index 6cb50347f..000000000 --- a/compiler/strutils2.nim +++ /dev/null @@ -1,57 +0,0 @@ -##[ -internal API for now, subject to modifications and moving around - -string API's focusing on performance, that can be used as building blocks -for other routines. - -Un-necessary allocations are avoided and appropriate algorithms are used at the -expense of code clarity when justified. -]## - -proc dataPointer*[T](a: T): pointer = - ## same as C++ `data` that works with std::string, std::vector etc. - ## Note: safe to use when a.len == 0 but whether the result is nil or not - ## is implementation defined for performance reasons. - # this could be improved with ocmpiler support to avoid the `if`, eg in C++ - # `&a[0]` is well defined even if a.size() == 0 - when T is string | seq: - if a.len == 0: nil else: cast[pointer](a[0].unsafeAddr) - elif T is array: - when a.len > 0: a.unsafeAddr - else: nil - elif T is cstring: - cast[pointer](a) - else: static: doAssert false, $T - -proc setLen*(result: var string, n: int, isInit: bool) = - ## when isInit = false, elements are left uninitialized, analog to `{.noinit.}` - ## else, there are 0-initialized. - # xxx placeholder until system.setLen supports this - # to distinguish between algorithms that need 0-initialization vs not; note - # that `setLen` for string is inconsistent with `setLen` for seq. - # likwise with `newString` vs `newSeq`. This should be fixed in `system`. - let n0 = result.len - result.setLen(n) - if isInit and n > n0: - zeroMem(result[n0].addr, n - n0) - -proc forceCopy*(result: var string, a: string) = - ## also forces a copy if `a` is shallow - # the naitve `result = a` would not work if `a` is shallow - let n = a.len - result.setLen n, isInit = false - copyMem(result.dataPointer, a.dataPointer, n) - -proc isUpperAscii(c: char): bool {.inline.} = - # avoids import strutils.isUpperAscii - c in {'A'..'Z'} - -proc toLowerAscii*(a: var string) = - ## optimized and inplace overload of strutils.toLowerAscii - # refs https://github.com/timotheecour/Nim/pull/54 - # this is 10X faster than a naive implementation using a an optimization trick - # that can be adapted in similar contexts. Predictable writes avoid write - # hazards and lead to better machine code, compared to random writes arising - # from: `if c.isUpperAscii: c = ...` - for c in mitems(a): - c = chr(c.ord + (if c.isUpperAscii: (ord('a') - ord('A')) else: 0)) |