===== Variable Name =====

==== In General ==== 
  * Avoid CamelCase and variation: use **underscore**
  * As short as possible to describe the "function" of the var: sample my $desc = "devmon is cool"

==== With or without "s" at the end ====
  * scalar($) and hash(%) without "s"
  * array(@) with an "s"

==== Avoid ambiguous names ====
  * last (final or previous)
  * set (adjust or collection)
  * left (direction or what remains)
  * right (direction, correct or entitlement)
  * no (negative:non or number)
  * record (verb or noun)
  * second (time or position)
  * close (nearby or shut)
  * use (active_usage or category of function)
  * term (terminal or termination)
  * temp (temperature or temporary)
  * val (value or valid)
  * **Avoid too short names** that dont give a real benefit: **prefer good readability**
  * prop(erty), val(ue), str(ing), num(ber), idx(index), but use it as postfix {variable}_XXX
  * i, j, k, x, y, z

==== Do not use ====
  * list, set, value, equals, data, var,

==== Quantity ====
  * scalar: {variable}_count
  * array : {variable}s_count (not a double "s" of course!)
  * hash: {variable}_count
  * linear Structure , hash, list ->{variable}_count ?
  * non-Linear Structure: tree, set: -> {variable}_count, ?

==== Prefix ====
  * format: as_number, as_string,
  * boolean: is_number

==== Reference ====
  * {variable}_ref


==== Quantity ====
Array