nix::Args Class Reference

Inheritance diagram for nix::Args:

Classes
struct	Handler
struct	Flag
struct	ExpectedArg

Public Member Functions
virtual std::string	description ()
virtual bool	forceImpureByDefault ()
virtual std::string	doc ()
virtual AsyncIoRoot &	aio ()=0
void	addFlag (Flag &&flag)
void	removeFlag (const std::string &longName)
void	expectArgs (ExpectedArg &&arg)
void	expectArg (const std::string &label, std::string *dest, bool optional=false)
void	expectArgs (const std::string &label, std::vector< std::string > *dest)
virtual JSON	toJSON ()
RootArgs &	getRoot ()

Public Attributes
MultiCommand *	parent = nullptr

Static Public Attributes
static CompleterFun	completePath
static CompleterFun	completeDir

Protected Types
typedef void	CompleterFun(AddCompletions &, size_t, std::string_view)
typedef std::function< CompleterFun >	CompleterClosure

Protected Member Functions
virtual bool	processFlag (Strings::iterator &pos, Strings::iterator end)
virtual bool	processArgs (const Strings &args, bool finish)
virtual Strings::iterator	rewriteArgs (Strings &args, Strings::iterator pos)
virtual void	initialFlagsProcessed ()
virtual std::optional< std::reference_wrapper< RootArgs > >	asRootArgs ()

Protected Attributes
std::map< std::string, Flag::ptr >	longFlags
std::map< char, Flag::ptr >	shortFlags
std::list< ExpectedArg >	expectedArgs
std::list< ExpectedArg >	processedArgs
std::set< std::string >	hiddenCategories

Static Protected Attributes
static const size_t	ArityAny = std::numeric_limits<size_t>::max()

Friends
class	MultiCommand

Member Typedef Documentation

CompleterClosure

typedef std::function<CompleterFun> nix::Args::CompleterClosure

protected

The closure type of the completion callback.

This is what is actually stored as part of each Flag / Expected Arg.

CompleterFun

typedef void nix::Args::CompleterFun(AddCompletions &, size_t, std::string_view)

protected

The basic function type of the completion callback.

Used to define CompleterClosure and some common case completers that individual flags/arguments can use.

The AddCompletions that is passed is an interface to the state stored as part of the root command

Member Function Documentation

asRootArgs()

virtual std::optional< std::reference_wrapper< RootArgs > > nix::Args::asRootArgs ( )

inlineprotectedvirtual

Returns this Args as a RootArgs if it is one, or std::nullopt otherwise.

description()

virtual std::string nix::Args::description ( )

inlinevirtual

Return a short one-line description of the command.

Reimplemented in nix::CmdAddDerivation, nix::CmdAddFile, nix::CmdAddPath, nix::CmdBuild, nix::CmdBundle, nix::CmdCatNar, nix::CmdCatStore, nix::CmdConfig, nix::CmdConfigShow, nix::CmdCopy, nix::CmdCopyLog, nix::CmdCopySigs, nix::CmdDaemon, nix::CmdDerivation, nix::CmdDevelop, nix::CmdDiffClosures, nix::CmdDoctor, nix::CmdDumpPath2, nix::CmdDumpPath, nix::CmdEdit, nix::CmdEval, nix::CmdFlake, nix::CmdFlakeArchive, nix::CmdFlakeCheck, nix::CmdFlakeClone, nix::CmdFlakeInit, nix::CmdFlakeLock, nix::CmdFlakeMetadata, nix::CmdFlakeNew, nix::CmdFlakePrefetch, nix::CmdFlakeShow, nix::CmdFlakeUpdate, nix::CmdFmt, nix::CmdHash, nix::CmdHashBase, nix::CmdHelp, nix::CmdHelpStores, nix::CmdKey, nix::CmdKeyConvertSecretToPublic, nix::CmdKeyGenerateSecret, nix::CmdLog, nix::CmdLsNar, nix::CmdLsStore, nix::CmdMakeContentAddressed, nix::CmdNar, nix::CmdOptimiseStore, nix::CmdPathFromHashPart, nix::CmdPathInfo, nix::CmdPingStore, nix::CmdPrintDevEnv, nix::CmdProfile, nix::CmdProfileDiffClosures, nix::CmdProfileHistory, nix::CmdProfileInstall, nix::CmdProfileList, nix::CmdProfileRemove, nix::CmdProfileRollback, nix::CmdProfileUpgrade, nix::CmdProfileWipeHistory, nix::CmdRealisation, nix::CmdRealisationInfo, nix::CmdRegistry, nix::CmdRegistryAdd, nix::CmdRegistryList, nix::CmdRegistryPin, nix::CmdRegistryRemove, nix::CmdRepl, nix::CmdRun, nix::CmdSearch, nix::CmdShell, nix::CmdShowDerivation, nix::CmdSign, nix::CmdStore, nix::CmdStoreDelete, nix::CmdStoreGC, nix::CmdStorePrefetchFile, nix::CmdStoreRepair, nix::CmdToBase, nix::CmdUpgradeNix, nix::CmdVerify, nix::CmdWhyDepends, and nix::NixArgs.

doc()

virtual std::string nix::Args::doc ( )

inlinevirtual

Return documentation about this command, in Markdown format.

Reimplemented in nix::CmdAddDerivation, nix::CmdAddFile, nix::CmdAddPath, nix::CmdBuild, nix::CmdBundle, nix::CmdCatNar, nix::CmdCatStore, nix::CmdCopy, nix::CmdCopyLog, nix::CmdDaemon, nix::CmdDevelop, nix::CmdDiffClosures, nix::CmdDumpPath2, nix::CmdDumpPath, nix::CmdEdit, nix::CmdEval, nix::CmdFlake, nix::CmdFlakeArchive, nix::CmdFlakeCheck, nix::CmdFlakeClone, nix::CmdFlakeInit, nix::CmdFlakeLock, nix::CmdFlakeMetadata, nix::CmdFlakeNew, nix::CmdFlakePrefetch, nix::CmdFlakeShow, nix::CmdFlakeUpdate, nix::CmdFmt, nix::CmdHelp, nix::CmdHelpStores, nix::CmdKeyConvertSecretToPublic, nix::CmdKeyGenerateSecret, nix::CmdLog, nix::CmdLsNar, nix::CmdLsStore, nix::CmdMakeContentAddressed, nix::CmdNar, nix::CmdOptimiseStore, nix::CmdPathFromHashPart, nix::CmdPathInfo, nix::CmdPingStore, nix::CmdPrintDevEnv, nix::CmdProfile, nix::CmdProfileDiffClosures, nix::CmdProfileHistory, nix::CmdProfileInstall, nix::CmdProfileList, nix::CmdProfileRemove, nix::CmdProfileRollback, nix::CmdProfileUpgrade, nix::CmdProfileWipeHistory, nix::CmdRealisationInfo, nix::CmdRegistry, nix::CmdRegistryAdd, nix::CmdRegistryList, nix::CmdRegistryPin, nix::CmdRegistryRemove, nix::CmdRepl, nix::CmdRun, nix::CmdSearch, nix::CmdShell, nix::CmdShowDerivation, nix::CmdStoreDelete, nix::CmdStoreGC, nix::CmdStorePrefetchFile, nix::CmdStoreRepair, nix::CmdUpgradeNix, nix::CmdVerify, nix::CmdWhyDepends, and nix::NixArgs.

expectArg()

void nix::Args::expectArg ( const std::string & label, std::string * dest, bool optional = false )

inline

Expect a string argument.

expectArgs()

void nix::Args::expectArgs ( const std::string & label, std::vector< std::string > * dest )

inline

Expect 0 or more arguments.

getRoot()

RootArgs & nix::Args::getRoot

(

)

Traverse parent pointers until we find the rootarguments object.

initialFlagsProcessed()

virtual void nix::Args::initialFlagsProcessed ( )

inlineprotectedvirtual

Called after all command line flags before the first non-flag argument (if any) have been processed.

processArgs()

bool nix::Args::processArgs ( const Strings & args, bool finish )

protectedvirtual

Process some positional arugments

Parameters

finish

We have parsed everything else, and these are the only arguments left. Used because we accumulate some "pending args" we might have left over.

Returns

true if the passed arguments were fully consumed and no further processing is required, false if the passed arguments should be processed with more context.

Reimplemented in nix::ExternalCommand, nix::LegacyArgs, and nix::MultiCommand.

processFlag()

bool nix::Args::processFlag ( Strings::iterator & pos, Strings::iterator end )

protectedvirtual

Process a single flag and its arguments, pulling from an iterator of raw CLI args as needed.

Returns

false if the flag is not recognised.

Reimplemented in nix::ExternalCommand, nix::LegacyArgs, and nix::MultiCommand.

Member Data Documentation

ArityAny

const size_t nix::Args::ArityAny = std::numeric_limits<size_t>::max()

staticprotected

The largest size_t is used to indicate the "any" arity, for handlers/flags/arguments that accept an arbitrary number of arguments.

expectedArgs

std::list<ExpectedArg> nix::Args::expectedArgs

protected

Queue of expected positional argument forms.

Positional argument descriptions are inserted on the back.

As positional arguments are passed, these are popped from the front, until there are hopefully none left as all args that were expected in fact were passed.

longFlags

std::map<std::string, Flag::ptr> nix::Args::longFlags

protected

Index of all registered "long" flag descriptions (flags like --long).

parent

MultiCommand* nix::Args::parent = nullptr

The parent command, used if this is a subcommand.

Invariant: An Args with a null parent must also be a RootArgs

Todo

this would probably be better in the CommandClass. getRoot() could be an abstract method that peels off at most one layer before recuring.

processedArgs

std::list<ExpectedArg> nix::Args::processedArgs

protected

List of processed positional argument forms.

All items removed from expectedArgs are added here. After all arguments were processed, this list should be exactly the same as expectedArgs was before.

This list is used to extend the lifetime of the argument forms. If this is not done, some closures that reference the command itself will segfault.

shortFlags

std::map<char, Flag::ptr> nix::Args::shortFlags

protected

Index of all registered "short" flag descriptions (flags like -s).

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The documentation for this class was generated from the following files:

• lix/libutil/args.hh
• lix/libutil/args.cc