diff options
| -rw-r--r-- | lib/pure/strutils.nim | 100 | ||||
| -rw-r--r-- | web/news.txt | 7 |
2 files changed, 86 insertions, 21 deletions
diff --git a/lib/pure/strutils.nim b/lib/pure/strutils.nim index 85e67f508..55494a8b5 100644 --- a/lib/pure/strutils.nim +++ b/lib/pure/strutils.nim @@ -1465,28 +1465,81 @@ proc formatFloat*(f: float, format: FloatFormatMode = ffDefault, ## after the decimal point for Nim's ``float`` type. result = formatBiggestFloat(f, format, precision, decimalSep) -proc formatSize*(bytes: BiggestInt, decimalSep = '.'): string = - ## Rounds and formats `bytes`. Examples: +proc trimZeros*(x: var string) {.noSideEffect.} = + ## Trim trailing zeros from a formatted floating point + ## value (`x`). Modifies the passed value. + var spl: seq[string] + if x.contains('.') or x.contains(','): + if x.contains('e'): + spl= x.split('e') + x = spl[0] + while x[x.high] == '0': + x.setLen(x.len-1) + if x[x.high] in [',', '.']: + x.setLen(x.len-1) + if spl.len > 0: + x &= "e" & spl[1] + +type + BinaryPrefixMode* = enum ## the different names for binary prefixes + bpIEC, # use the IEC/ISO standard prefixes such as kibi + bpColloquial # use the colloquial kilo, mega etc + +proc formatSize*(bytes: int64, + decimalSep = '.', + prefix = bpIEC, + includeSpace = false): string = + ## Rounds and formats `bytes`. + ## + ## By default, uses the IEC/ISO standard binary prefixes, so 1024 will be + ## formatted as 1KiB. Set prefix to `bpColloquial` to use the colloquial + ## names from the SI standard (e.g. k for 1000 being reused as 1024). + ## + ## `includeSpace` can be set to true to include the (SI preferred) space + ## between the number and the unit (e.g. 1 KiB). + ## + ## Examples: ## ## .. code-block:: nim ## - ## formatSize(1'i64 shl 31 + 300'i64) == "2.204GB" - ## formatSize(4096) == "4KB" - ## - template frmt(a, b, c: expr): expr = - let bs = $b - insertSep($a) & decimalSep & bs.substr(0, 2) & c - let gigabytes = bytes shr 30 - let megabytes = bytes shr 20 - let kilobytes = bytes shr 10 - if gigabytes != 0: - result = frmt(gigabytes, megabytes, "GB") - elif megabytes != 0: - result = frmt(megabytes, kilobytes, "MB") - elif kilobytes != 0: - result = frmt(kilobytes, bytes, "KB") + ## formatSize((1'i64 shl 31) + (300'i64 shl 20)) == "2.293GiB" + ## formatSize((2.234*1024*1024).int) == "2.234MiB" + ## formatSize(4096, includeSpace=true) == "4 KiB" + ## formatSize(4096, prefix=bpColloquial, includeSpace=true) == "4 kB" + ## formatSize(4096) == "4KiB" + ## formatSize(5_378_934, prefix=bpColloquial, decimalSep=',') == "5,13MB" + ## + const iecPrefixes = ["", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi", "Yi"] + const collPrefixes = ["", "k", "M", "G", "T", "P", "E", "Z", "Y"] + var + xb: int64 = bytes + fbytes: float + last_xb: int64 = bytes + matchedIndex: int + prefixes: array[9, string] + if prefix == bpColloquial: + prefixes = collPrefixes else: - result = insertSep($bytes) & "B" + prefixes = iecPrefixes + + # Iterate through prefixes seeing if value will be greater than + # 0 in each case + for index in 1..<prefixes.len: + last_xb = xb + xb = bytes div (1'i64 shl (index*10)) + matchedIndex = index + if xb == 0: + xb = last_xb + matchedIndex = index - 1 + break + # xb has the integer number for the latest value; index should be correct + fbytes = bytes.float / (1'i64 shl (matchedIndex*10)).float + result = formatFloat(fbytes, format=ffDecimal, precision=3, decimalSep=decimalSep) + result.trimZeros() + if includeSpace: + result &= " " + result &= prefixes[matchedIndex] + result &= "B" proc findNormalized(x: string, inArray: openArray[string]): int = var i = 0 @@ -1682,9 +1735,14 @@ when isMainModule: ["1,0e-11", "1,0e-011"] doAssert "$# $3 $# $#" % ["a", "b", "c"] == "a c b c" - when not defined(testing): - echo formatSize(1'i64 shl 31 + 300'i64) # == "4,GB" - echo formatSize(1'i64 shl 31) + + block: # formatSize tests + doAssert formatSize((1'i64 shl 31) + (300'i64 shl 20)) == "2.293GiB" + doAssert formatSize((2.234*1024*1024).int) == "2.234MiB" + doAssert formatSize(4096) == "4KiB" + doAssert formatSize(4096, prefix=bpColloquial, includeSpace=true) == "4 kB" + doAssert formatSize(4096, includeSpace=true) == "4 KiB" + doAssert formatSize(5_378_934, prefix=bpColloquial, decimalSep=',') == "5,13MB" doAssert "$animal eats $food." % ["animal", "The cat", "food", "fish"] == "The cat eats fish." diff --git a/web/news.txt b/web/news.txt index 3290baa5c..2ede07151 100644 --- a/web/news.txt +++ b/web/news.txt @@ -50,6 +50,11 @@ Changes affecting backwards compatibility than changing the operation for even and odd numbers. - The ``round`` function now accepts a ``places`` argument to round to a given number of places (e.g. round 4.35 to 4.4 if ``places`` is 1). +- In ``strutils.nim``, ``formatSize`` now returns a number representing the + size in conventional decimal format (e.g. 2.234GB meaning 2.234 GB rather + than meaning 2.285 GB as in the previous implementation). By default it + also uses IEC prefixes (KiB, MiB) etc and optionally uses colloquial names + (kB, MB etc) and the (SI-preferred) space. Library Additions @@ -63,6 +68,8 @@ Library Additions versions are for ``char`` and ``set[char]``. - Added ``splitDecimal`` to ``math.nim`` to split a floating point value into an integer part and a floating part (in the range -1<x<1). +- Added ``trimZeros`` to ```strutils.nim`` to trim trailing zeros in a + floating point number. Compiler Additions |