Replace --Norm with general but reasonably efficient --format using

`cligen/strUt` templating & fcvt float formatting.

util/lfreq.nim

@@ -1,5 +1,6 @@
 when not declared(stdin): import std/[syncio, formatfloat]
-import std/[hashes,times,sugar,algorithm], cligen,cligen/[mslice,osUt],adix/oats
+import std/[hashes, times, sugar, algorithm, strutils],
+ cligen, cligen/[mslice, strUt, osUt], adix/oats
 
 const bLen {.intdefine.} = 16 # <16K long; RT params better but more work
 const bOff {.intdefine.} = 32 # <4G UNIQUE line data
@@ -41,8 +42,8 @@ proc incFailed(h: var Counts, ms: MSlice): bool =
  h.dat[i].len = ms.len.uint32# Init
  h.dat[i].cnt = 1u32
 
-proc lfreq(n=10, count=false,Norm=false, size=9999,dSize=81920,
- recTerm='\n',RecTerm="\n", tm=false) =
+proc lfreq(n=10, count=false, size=9999, dSize=81920, recTerm='\n',
+ format="@c @k", RecTerm="\n", tm=false) =
  ## Histogram `stdin` lines (read w/non-memory mapped IO to be pipe friendly).
  ## Limits: <4 GiB unique data; <16 KiB lines; <4 GiCount.
  let t0 = if tm: epochTime() else: 0.0
@@ -55,8 +56,16 @@ proc lfreq(n=10, count=false,Norm=false, size=9999,dSize=81920,
  inc nTot # Always bump `nTotal`
  if h.incFailed(ms): break IO
  if count: outu h.len," unique ",nTot," total ",s.len," B\n"
+ let nInv = 1.0/nTot.float; var cs, fs: string # Setup for..
+ let prs = format.tmplParsed('@') #..nice output
  template output =
- if Norm: outu c.float/nTot.float," ",k,RecTerm else: outu c," ",k,RecTerm
+ for (id, arg, call) in prs:
+ if id.idIsLiteral: outu MSlice(mem: format[arg.a].addr, len: arg.len)
+ elif format[id.a] == 'c': cs.setLen 0; cs.addInt c; outu cs
+ elif format[id.a] == 'k': outu k
+ elif format[id.a] == 'f': fs.setLen 0; fs.fcvt c.float*nInv, 9; outu fs
+ else: outu MSlice(mem: format[call.a].addr, len: call.len)
+ outu RecTerm
  if n == 0: (for (k, c) in pairs(h): output())
  elif n > 0: (for (k, c) in h.topByVal(n): output())
  elif n < -1: # -1 is same as +1; Hijack value to mean no output()
@@ -67,9 +76,9 @@ proc lfreq(n=10, count=false,Norm=false, size=9999,dSize=81920,
 when isMainModule: dispatch lfreq, help={
  "n" : "only emit most frequent `n` lines(!=0=>sorted)",
  "count": "only emit counts: unique & grand total",
- "Norm" : "normalize frequencies by dividing by grand tot",
  "size" : "pre-size hash table for size unique entries",
  "dSize": "pre-size str data area to this many bytes",
  "recTerm": "input record terminator",
  "RecTerm": "output record terminator",
+ "format" : "output format: $k=key $c=count $f=fraction",
  "tm" : "emit wall time of counting to stderr & quit"}