Add basic support for ANSI color escape codes.

Nim's `terminal` library provides ANSI terminal escape support, but
only when writing directly to a File handle. This commit adds the
`term{FG,BG}` procedures and `termReset` constant to help with embedding
ANSI escape codes in string data.

cliutils.nim

@@ -1,5 +1,7 @@
-import docopt, json, osproc, posix, nre, streams, strutils, strtabs
+import docopt, json, osproc, posix, nre, streams, strtabs, terminal, unicode
 import os except sleep
+import strutils except toUpper, toLower
+
 
 type
   CombinedConfig* = object
@@ -13,7 +15,16 @@ proc getVal*(cfg: CombinedConfig, key, default: string): string =
 
   if cfg.docopt[argKey]: return $cfg.docopt[argKey]
   elif existsEnv(envKey): return getEnv(envKey)
-  elif cfg.json.hasKey(jsonKey): return cfg.json[jsonKey].getStr
+  elif cfg.json.hasKey(jsonKey):
+    let node = cfg.json[jsonKey]
+    case node.kind
+    of JString: return node.getStr
+    of JInt: return $node.getInt
+    of JFloat: return $node.getFloat
+    of JBool: return $node.getBool
+    of JNull: return ""
+    of JObject: return $node
+    of JArray: return $node
   else: return default
 
 
@@ -71,7 +82,7 @@ proc exec*(command: string, workingDir: string = "",
            args: openArray[string] = [], env: StringTableRef = nil,
            options: set[ProcessOption] = {poUsePath},
            msgCB: HandleProcMsgCB = nil): int
-    {.tags: [ExecIOEffect, ReadIOEffect], gcsafe.} =
+    {.tags: [ExecIOEffect, ReadIOEffect, RootEffect], gcsafe.} =
 
   var p = startProcess(command, workingDir, args, env, options)
   result = waitFor(p, msgCB, command)
@@ -108,7 +119,7 @@ proc onStop(sig: cint) {.noconv.} =
 
   quit(QuitSuccess)
 
-proc daemonize*(pidfile, si, so, se: string, daemonMain: proc(): void): int =
+proc daemonize*(pidfile, si, so, se: string, daemonMain: proc(): void): Pid =
 
   if fileExists(pidfile):
     raise newException(IOError, "pidfile " & pidfile & " already exists, daemon already running?")
@@ -160,3 +171,15 @@ proc daemonize*(pidfile, si, so, se: string, daemonMain: proc(): void): int =
     daemonMain()
 
   return pid1
+
+proc termFG*(color: ForegroundColor, bright, bold = false): string =
+  var colorVal = ord(color)
+  if bright: inc(colorVal, 60)
+  return "\e[" & $colorVal & (if bold: ";1" else: "") & "m"
+
+proc termBG*(color: BackgroundColor, bright, bold = false): string =
+  var colorVal = ord(color)
+  if bright: inc(colorVal, 60)
+  return "\e[" & $colorVal & "m"
+
+const termReset* = "\e[0;m"

cliutils.nimble

@@ -1,11 +1,11 @@
 # Package
 
-version       = "0.3.0"
+version       = "0.4.0"
 author        = "Jonathan Bernard"
 description   = "Helper functions for writing command line interfaces."
 license       = "MIT"
 
 # Dependencies
 
-requires @["nim >= 0.15.3", "docopt"]
+requires @["nim >= 0.18.0", "docopt"]