diff options
Diffstat (limited to 'src/pkg/flag/flag.go')
| -rw-r--r-- | src/pkg/flag/flag.go | 113 |
1 files changed, 75 insertions, 38 deletions
diff --git a/src/pkg/flag/flag.go b/src/pkg/flag/flag.go index 85dd8c3b3..e7c863ee9 100644 --- a/src/pkg/flag/flag.go +++ b/src/pkg/flag/flag.go @@ -89,6 +89,8 @@ func (b *boolValue) Set(s string) error { return err } +func (b *boolValue) Get() interface{} { return bool(*b) } + func (b *boolValue) String() string { return fmt.Sprintf("%v", *b) } func (b *boolValue) IsBoolFlag() bool { return true } @@ -114,6 +116,8 @@ func (i *intValue) Set(s string) error { return err } +func (i *intValue) Get() interface{} { return int(*i) } + func (i *intValue) String() string { return fmt.Sprintf("%v", *i) } // -- int64 Value @@ -130,6 +134,8 @@ func (i *int64Value) Set(s string) error { return err } +func (i *int64Value) Get() interface{} { return int64(*i) } + func (i *int64Value) String() string { return fmt.Sprintf("%v", *i) } // -- uint Value @@ -146,6 +152,8 @@ func (i *uintValue) Set(s string) error { return err } +func (i *uintValue) Get() interface{} { return uint(*i) } + func (i *uintValue) String() string { return fmt.Sprintf("%v", *i) } // -- uint64 Value @@ -162,6 +170,8 @@ func (i *uint64Value) Set(s string) error { return err } +func (i *uint64Value) Get() interface{} { return uint64(*i) } + func (i *uint64Value) String() string { return fmt.Sprintf("%v", *i) } // -- string Value @@ -177,6 +187,8 @@ func (s *stringValue) Set(val string) error { return nil } +func (s *stringValue) Get() interface{} { return string(*s) } + func (s *stringValue) String() string { return fmt.Sprintf("%s", *s) } // -- float64 Value @@ -193,6 +205,8 @@ func (f *float64Value) Set(s string) error { return err } +func (f *float64Value) Get() interface{} { return float64(*f) } + func (f *float64Value) String() string { return fmt.Sprintf("%v", *f) } // -- time.Duration Value @@ -209,6 +223,8 @@ func (d *durationValue) Set(s string) error { return err } +func (d *durationValue) Get() interface{} { return time.Duration(*d) } + func (d *durationValue) String() string { return (*time.Duration)(d).String() } // Value is the interface to the dynamic value stored in a flag. @@ -222,6 +238,15 @@ type Value interface { Set(string) error } +// Getter is an interface that allows the contents of a Value to be retrieved. +// It wraps the Value interface, rather than being part of it, because it +// appeared after Go 1 and its compatibility rules. All Value types provided +// by this package satisfy the Getter interface. +type Getter interface { + Value + Get() interface{} +} + // ErrorHandling defines how to handle flag parsing errors. type ErrorHandling int @@ -231,7 +256,8 @@ const ( PanicOnError ) -// A FlagSet represents a set of defined flags. +// A FlagSet represents a set of defined flags. The zero value of a FlagSet +// has no name and has ContinueOnError error handling. type FlagSet struct { // Usage is the function called when an error occurs while parsing flags. // The field is a function (not a method) that may be changed to point to @@ -296,7 +322,7 @@ func (f *FlagSet) VisitAll(fn func(*Flag)) { // VisitAll visits the command-line flags in lexicographical order, calling // fn for each. It visits all flags, even those not set. func VisitAll(fn func(*Flag)) { - commandLine.VisitAll(fn) + CommandLine.VisitAll(fn) } // Visit visits the flags in lexicographical order, calling fn for each. @@ -310,7 +336,7 @@ func (f *FlagSet) Visit(fn func(*Flag)) { // Visit visits the command-line flags in lexicographical order, calling fn // for each. It visits only those flags that have been set. func Visit(fn func(*Flag)) { - commandLine.Visit(fn) + CommandLine.Visit(fn) } // Lookup returns the Flag structure of the named flag, returning nil if none exists. @@ -321,7 +347,7 @@ func (f *FlagSet) Lookup(name string) *Flag { // Lookup returns the Flag structure of the named command-line flag, // returning nil if none exists. func Lookup(name string) *Flag { - return commandLine.formal[name] + return CommandLine.formal[name] } // Set sets the value of the named flag. @@ -343,7 +369,7 @@ func (f *FlagSet) Set(name, value string) error { // Set sets the value of the named command-line flag. func Set(name, value string) error { - return commandLine.Set(name, value) + return CommandLine.Set(name, value) } // PrintDefaults prints, to standard error unless configured @@ -361,16 +387,20 @@ func (f *FlagSet) PrintDefaults() { // PrintDefaults prints to standard error the default values of all defined command-line flags. func PrintDefaults() { - commandLine.PrintDefaults() + CommandLine.PrintDefaults() } // defaultUsage is the default function to print a usage message. func defaultUsage(f *FlagSet) { - fmt.Fprintf(f.out(), "Usage of %s:\n", f.name) + if f.name == "" { + fmt.Fprintf(f.out(), "Usage:\n") + } else { + fmt.Fprintf(f.out(), "Usage of %s:\n", f.name) + } f.PrintDefaults() } -// NOTE: Usage is not just defaultUsage(commandLine) +// NOTE: Usage is not just defaultUsage(CommandLine) // because it serves (via godoc flag Usage) as the example // for how to write your own usage function. @@ -385,7 +415,7 @@ var Usage = func() { func (f *FlagSet) NFlag() int { return len(f.actual) } // NFlag returns the number of command-line flags that have been set. -func NFlag() int { return len(commandLine.actual) } +func NFlag() int { return len(CommandLine.actual) } // Arg returns the i'th argument. Arg(0) is the first remaining argument // after flags have been processed. @@ -399,20 +429,20 @@ func (f *FlagSet) Arg(i int) string { // Arg returns the i'th command-line argument. Arg(0) is the first remaining argument // after flags have been processed. func Arg(i int) string { - return commandLine.Arg(i) + return CommandLine.Arg(i) } // NArg is the number of arguments remaining after flags have been processed. func (f *FlagSet) NArg() int { return len(f.args) } // NArg is the number of arguments remaining after flags have been processed. -func NArg() int { return len(commandLine.args) } +func NArg() int { return len(CommandLine.args) } // Args returns the non-flag arguments. func (f *FlagSet) Args() []string { return f.args } // Args returns the non-flag command-line arguments. -func Args() []string { return commandLine.args } +func Args() []string { return CommandLine.args } // BoolVar defines a bool flag with specified name, default value, and usage string. // The argument p points to a bool variable in which to store the value of the flag. @@ -423,7 +453,7 @@ func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string) { // BoolVar defines a bool flag with specified name, default value, and usage string. // The argument p points to a bool variable in which to store the value of the flag. func BoolVar(p *bool, name string, value bool, usage string) { - commandLine.Var(newBoolValue(value, p), name, usage) + CommandLine.Var(newBoolValue(value, p), name, usage) } // Bool defines a bool flag with specified name, default value, and usage string. @@ -437,7 +467,7 @@ func (f *FlagSet) Bool(name string, value bool, usage string) *bool { // Bool defines a bool flag with specified name, default value, and usage string. // The return value is the address of a bool variable that stores the value of the flag. func Bool(name string, value bool, usage string) *bool { - return commandLine.Bool(name, value, usage) + return CommandLine.Bool(name, value, usage) } // IntVar defines an int flag with specified name, default value, and usage string. @@ -449,7 +479,7 @@ func (f *FlagSet) IntVar(p *int, name string, value int, usage string) { // IntVar defines an int flag with specified name, default value, and usage string. // The argument p points to an int variable in which to store the value of the flag. func IntVar(p *int, name string, value int, usage string) { - commandLine.Var(newIntValue(value, p), name, usage) + CommandLine.Var(newIntValue(value, p), name, usage) } // Int defines an int flag with specified name, default value, and usage string. @@ -463,7 +493,7 @@ func (f *FlagSet) Int(name string, value int, usage string) *int { // Int defines an int flag with specified name, default value, and usage string. // The return value is the address of an int variable that stores the value of the flag. func Int(name string, value int, usage string) *int { - return commandLine.Int(name, value, usage) + return CommandLine.Int(name, value, usage) } // Int64Var defines an int64 flag with specified name, default value, and usage string. @@ -475,7 +505,7 @@ func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string) { // Int64Var defines an int64 flag with specified name, default value, and usage string. // The argument p points to an int64 variable in which to store the value of the flag. func Int64Var(p *int64, name string, value int64, usage string) { - commandLine.Var(newInt64Value(value, p), name, usage) + CommandLine.Var(newInt64Value(value, p), name, usage) } // Int64 defines an int64 flag with specified name, default value, and usage string. @@ -489,7 +519,7 @@ func (f *FlagSet) Int64(name string, value int64, usage string) *int64 { // Int64 defines an int64 flag with specified name, default value, and usage string. // The return value is the address of an int64 variable that stores the value of the flag. func Int64(name string, value int64, usage string) *int64 { - return commandLine.Int64(name, value, usage) + return CommandLine.Int64(name, value, usage) } // UintVar defines a uint flag with specified name, default value, and usage string. @@ -501,7 +531,7 @@ func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string) { // UintVar defines a uint flag with specified name, default value, and usage string. // The argument p points to a uint variable in which to store the value of the flag. func UintVar(p *uint, name string, value uint, usage string) { - commandLine.Var(newUintValue(value, p), name, usage) + CommandLine.Var(newUintValue(value, p), name, usage) } // Uint defines a uint flag with specified name, default value, and usage string. @@ -515,7 +545,7 @@ func (f *FlagSet) Uint(name string, value uint, usage string) *uint { // Uint defines a uint flag with specified name, default value, and usage string. // The return value is the address of a uint variable that stores the value of the flag. func Uint(name string, value uint, usage string) *uint { - return commandLine.Uint(name, value, usage) + return CommandLine.Uint(name, value, usage) } // Uint64Var defines a uint64 flag with specified name, default value, and usage string. @@ -527,7 +557,7 @@ func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string) // Uint64Var defines a uint64 flag with specified name, default value, and usage string. // The argument p points to a uint64 variable in which to store the value of the flag. func Uint64Var(p *uint64, name string, value uint64, usage string) { - commandLine.Var(newUint64Value(value, p), name, usage) + CommandLine.Var(newUint64Value(value, p), name, usage) } // Uint64 defines a uint64 flag with specified name, default value, and usage string. @@ -541,7 +571,7 @@ func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64 { // Uint64 defines a uint64 flag with specified name, default value, and usage string. // The return value is the address of a uint64 variable that stores the value of the flag. func Uint64(name string, value uint64, usage string) *uint64 { - return commandLine.Uint64(name, value, usage) + return CommandLine.Uint64(name, value, usage) } // StringVar defines a string flag with specified name, default value, and usage string. @@ -553,7 +583,7 @@ func (f *FlagSet) StringVar(p *string, name string, value string, usage string) // StringVar defines a string flag with specified name, default value, and usage string. // The argument p points to a string variable in which to store the value of the flag. func StringVar(p *string, name string, value string, usage string) { - commandLine.Var(newStringValue(value, p), name, usage) + CommandLine.Var(newStringValue(value, p), name, usage) } // String defines a string flag with specified name, default value, and usage string. @@ -567,7 +597,7 @@ func (f *FlagSet) String(name string, value string, usage string) *string { // String defines a string flag with specified name, default value, and usage string. // The return value is the address of a string variable that stores the value of the flag. func String(name string, value string, usage string) *string { - return commandLine.String(name, value, usage) + return CommandLine.String(name, value, usage) } // Float64Var defines a float64 flag with specified name, default value, and usage string. @@ -579,7 +609,7 @@ func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage strin // Float64Var defines a float64 flag with specified name, default value, and usage string. // The argument p points to a float64 variable in which to store the value of the flag. func Float64Var(p *float64, name string, value float64, usage string) { - commandLine.Var(newFloat64Value(value, p), name, usage) + CommandLine.Var(newFloat64Value(value, p), name, usage) } // Float64 defines a float64 flag with specified name, default value, and usage string. @@ -593,7 +623,7 @@ func (f *FlagSet) Float64(name string, value float64, usage string) *float64 { // Float64 defines a float64 flag with specified name, default value, and usage string. // The return value is the address of a float64 variable that stores the value of the flag. func Float64(name string, value float64, usage string) *float64 { - return commandLine.Float64(name, value, usage) + return CommandLine.Float64(name, value, usage) } // DurationVar defines a time.Duration flag with specified name, default value, and usage string. @@ -605,7 +635,7 @@ func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration // DurationVar defines a time.Duration flag with specified name, default value, and usage string. // The argument p points to a time.Duration variable in which to store the value of the flag. func DurationVar(p *time.Duration, name string, value time.Duration, usage string) { - commandLine.Var(newDurationValue(value, p), name, usage) + CommandLine.Var(newDurationValue(value, p), name, usage) } // Duration defines a time.Duration flag with specified name, default value, and usage string. @@ -619,7 +649,7 @@ func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time // Duration defines a time.Duration flag with specified name, default value, and usage string. // The return value is the address of a time.Duration variable that stores the value of the flag. func Duration(name string, value time.Duration, usage string) *time.Duration { - return commandLine.Duration(name, value, usage) + return CommandLine.Duration(name, value, usage) } // Var defines a flag with the specified name and usage string. The type and @@ -633,7 +663,12 @@ func (f *FlagSet) Var(value Value, name string, usage string) { flag := &Flag{name, usage, value, value.String()} _, alreadythere := f.formal[name] if alreadythere { - msg := fmt.Sprintf("%s flag redefined: %s", f.name, name) + var msg string + if f.name == "" { + msg = fmt.Sprintf("flag redefined: %s", name) + } else { + msg = fmt.Sprintf("%s flag redefined: %s", f.name, name) + } fmt.Fprintln(f.out(), msg) panic(msg) // Happens only if flags are declared with identical names } @@ -650,7 +685,7 @@ func (f *FlagSet) Var(value Value, name string, usage string) { // of strings by giving the slice the methods of Value; in particular, Set would // decompose the comma-separated string into the slice. func Var(value Value, name string, usage string) { - commandLine.Var(value, name, usage) + CommandLine.Var(value, name, usage) } // failf prints to standard error a formatted error and usage message and @@ -663,9 +698,9 @@ func (f *FlagSet) failf(format string, a ...interface{}) error { } // usage calls the Usage method for the flag set, or the usage function if -// the flag set is commandLine. +// the flag set is CommandLine. func (f *FlagSet) usage() { - if f == commandLine { + if f == CommandLine { Usage() } else if f.Usage == nil { defaultUsage(f) @@ -674,7 +709,7 @@ func (f *FlagSet) usage() { } } -// parseOne parses one flag. It returns whether a flag was seen. +// parseOne parses one flag. It reports whether a flag was seen. func (f *FlagSet) parseOne() (bool, error) { if len(f.args) == 0 { return false, nil @@ -781,17 +816,19 @@ func (f *FlagSet) Parsed() bool { // Parse parses the command-line flags from os.Args[1:]. Must be called // after all flags are defined and before flags are accessed by the program. func Parse() { - // Ignore errors; commandLine is set for ExitOnError. - commandLine.Parse(os.Args[1:]) + // Ignore errors; CommandLine is set for ExitOnError. + CommandLine.Parse(os.Args[1:]) } // Parsed returns true if the command-line flags have been parsed. func Parsed() bool { - return commandLine.Parsed() + return CommandLine.Parsed() } -// The default set of command-line flags, parsed from os.Args. -var commandLine = NewFlagSet(os.Args[0], ExitOnError) +// CommandLine is the default set of command-line flags, parsed from os.Args. +// The top-level functions such as BoolVar, Arg, and on are wrappers for the +// methods of CommandLine. +var CommandLine = NewFlagSet(os.Args[0], ExitOnError) // NewFlagSet returns a new, empty flag set with the specified name and // error handling property. |