[Complement-devel] Grammar of command-line options

[Petr O. <pt...@is...>]

[Extracted from Dmitry's post]:

Command line representation:

Notes:
'{','}','+','!' - are not terms, that are no so formal:
	'{','}' = grouping concepts
	'+' = at the same time
	"!=" = not equal to
	"T[]" = array of type T

Grammar:
	* alnum = 'a' - 'z' || 'A' - 'Z' || '1' - '9'
	* word = string + !' '
	* shortname = -alnum
	* longname = --{char[] + !='='}
	* basicname = shortname || longname
	* reduction = longname.substr(0,k) : there are no two longnames with that substr
	* optname = basicname || reduction
	* arg = word || "string" // argument must be represented as single element of argv[]
	* option = optname || optname arg || optname=word 
	* optiongroup = -alnum[] 
	* operand = word
	* end = "--"
	* commandline = utility_name [option...] [optiongroup ...] [end operand ...]

Errors:
	* invalid option - optname
	* missing param - optname