args

Documentation

Index

• type FlagResult
• type PrefixOption
• type Scanner
  • func (s *Scanner) HasNext() bool
  • func (s *Scanner) LookAhead() string
  • func (s *Scanner) Next() (string, []string, []string, bool)
  • func (s *Scanner) ReadNextFlag() *FlagResult

Types

type FlagResult

type FlagResult struct {
	Args          []string
	NormalizedKey string
	OriginalKey   string
	Values        []string
	Joined        bool
}

FlagResult is a result of Scanner's Next operation

type PrefixOption

type PrefixOption struct {
	Prefix  string
	NumArgs int
}

PrefixOption is option for joined flags.

type Scanner

type Scanner struct {
	// Args is remaining arguments.
	Args []string

	// Flags are map keyed by -flag and number of argments for the flag.
	// The flag requires additional value from args if value > 0.
	// The flag doesn't require additional value from args if value == 0
	Flags map[string]int

	// Joined are prefixes of flag that has value in the same arg.
	// sorted Prefixes by reverse lexicographic order.
	Joined []PrefixOption

	// flag normalization.
	Normalized map[string]string

	// PrevResult is the previous Flag Result that has been handled.
	PrevResult FlagResult

	// CurResult is the current Flag Result being processed.
	CurResult FlagResult
}

Scanner scans command line arguments. it scans args and gets (flag, args, value) in each Next call.

for `-flagname`, it is recognized as flag by default, and it returns ("-flagname", ["-flagname"], nil).

for `-flagnameflagvalue`, need to set "-flagname" in joined, and it returns ("-flagname", ["-flagnameflagvalue"], ["flagvalue"]).

for `-flagname flagvalue`, need to set flags["-flagname"] = 1, and it returns ("-flagname", ["-flagname", "flagvalue"], ["flagvalue"]).

for non-flag "parameter", it returns ("", ["parameter"], nil).

if "-flagname" is used for both `-flagnameflagvalue`, `-flagname flagvalue`, need to set it both in joined and flags.

to accept "/flagname", need to use "/flagname" for flags, joined.

for `--flagname`, need to use "--flagname" for flags, joined.

func (*Scanner) HasNext

func (s *Scanner) HasNext() bool

HasNext returns true if there is more args to process.

func (*Scanner) LookAhead

func (s *Scanner) LookAhead() string

LookAhead looks ahead next flag.

func (*Scanner) Next

func (s *Scanner) Next() (string, []string, []string, bool)

Next returns next flag. flag is normalized flag, empty string if not started with "-". args are consumed arguments. values are flag value if flag needs value (next arg in args) or joined (rest after prefix in the arg).

func (*Scanner) ReadNextFlag

func (s *Scanner) ReadNextFlag() *FlagResult

ReadNextFlag moves forward the current FlagResult, update the scanner's PrevResult, and CurResult fields, and return the CurResult. NormalizedKey is normalized flag, or empty string if not started with "-". OriginalKey is a key before the normalization Args are consumed arguments. Values are flag value if flag needs value (next arg in args) or Joined (rest after prefix in the arg).