ns_env Namespace Reference

Environment variable management utilities. More...

Enumerations
enum class	Replace { Y , N }

Functions
template<ns_concept::StringRepresentable T, ns_concept::StringRepresentable U>
void	set (T &&name, U &&value, Replace replace)
	Sets an environment variable.
template<ns_string::static_string S = "E">
Value< std::string >	get_expected (std::string_view name)
	Get the value of an environment variable.
bool	exists (std::string_view name, std::string_view value)
	Checks if variable exists and equals value.
Value< std::string >	expand (ns_concept::StringRepresentable auto &&var)
	Performs variable expansion analogous to a POSIX shell.
template<typename T = std::string>
Value< T >	xdg_data_home () noexcept
	Returns or computes the value of XDG_DATA_HOME.
Value< fs::path >	search_path (std::string const &query)
	Search the directories in the PATH variable for the given input file name.

Detailed Description

Environment variable management utilities.

Provides type-safe environment variable operations including get/set with default values, PATH searching for executables, variable expansion, and existence checking.

Enumeration Type Documentation

Replace

enum class ns_env::Replace

strong

Definition at line 36 of file env.hpp.

Function Documentation

exists()

bool ns_env::exists ( std::string_view name, std::string_view value )

inline

Checks if variable exists and equals value.

Parameters

name	Name of the variable
value	Value value of the variable

Returns

True if it exists and matches the expected value, or false otherwise

Definition at line 82 of file env.hpp.

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expand()

Value< std::string > ns_env::expand ( ns_concept::StringRepresentable auto && var )

inline

Performs variable expansion analogous to a POSIX shell.

Template Parameters

auto	Type that is string representable (constrained by concept)

Parameters

var	Source string to expand

Returns

Value<std::string> The expanded value or the respective error

Examples

/flatimage/src/filesystems/layers.hpp.

Definition at line 96 of file env.hpp.

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get_expected()

template<ns_string::static_string S = "E">

Value< std::string > ns_env::get_expected ( std::string_view name )

inline

Get the value of an environment variable.

Template Parameters

T	The output type of the function

Parameters

name	The name of the variable

Returns

Value<std::string> The value of the variable or the respective error

Examples

/flatimage/src/filesystems/layers.hpp.

Definition at line 65 of file env.hpp.

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search_path()

Value< fs::path > ns_env::search_path ( std::string const & query )

inlinenodiscard

Search the directories in the PATH variable for the given input file name.

Parameters

query

The file name to search for in PATH directories

Returns

Value<fs::path> The path of the found file or the respective error

Definition at line 150 of file env.hpp.

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set()

template<ns_concept::StringRepresentable T, ns_concept::StringRepresentable U>

void ns_env::set	(	T &&	name,
		U &&	value,
		Replace	replace )

Sets an environment variable.

Template Parameters

T	StringRepresentable
U	StringRepresentable

Parameters

name	Variable name
value	Variable value
replace	Should it be replace if it exists?

Definition at line 52 of file env.hpp.

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xdg_data_home()

template<typename T = std::string>

Value< T > ns_env::xdg_data_home ( )

inlinenoexcept

Returns or computes the value of XDG_DATA_HOME.

Template Parameters

T	The return type for the path (defaults to std::string, can be fs::path or other string-convertible types)

Returns

Value<T> The path to XDG_DATA_HOME or the respective error

Definition at line 135 of file env.hpp.

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