EnvExpander Class Reference

#include <ArmarXCore/core/system/EnvExpander.h>

Public Types
enum class	Operation : std::uint8_t { Replace , Append , Prepend }

Public Member Functions
void	apply (const std::string &input, bool expandExisting=true)
	Parse and apply the comma-separated assignment list to the internal environment env_ and to the process environment via setenv.
void	applyOperation (const std::string &name, Operation op, const std::string &val)
	EnvExpander ()
	Construct an EnvExpander initialized with the current process environment.

Static Public Member Functions
static std::string	expand (const std::string &input)
	Return the expanded form of the comma-separated assignment list without modifying the process environment.
static std::string	expandVariables (const std::string &value)
static std::vector< std::string >	splitAssignments (const std::string &input)
static std::tuple< std::string, Operation, std::string >	splitOperation (const std::string &assignment)

Public Attributes
boost::process::environment	env_

Member Enumeration Documentation

Operation

enum class Operation : std::uint8_t

strong

Enumerator
Replace
Append
Prepend

Constructor & Destructor Documentation

EnvExpander()

EnvExpander

(

)

Construct an EnvExpander initialized with the current process environment.

The instance keeps a working copy of the environment (stored in env_) which apply() will update when assignments are applied. This allows expansions to optionally see earlier changes.

Member Function Documentation

apply()

void apply	(	const std::string &	input,
		bool	expandExisting = true )

Parse and apply the comma-separated assignment list to the internal environment env_ and to the process environment via setenv.

The input format is a comma-separated list of assignments. Each assignment may be a replace (NAME=val), append (NAME+=val) or prepend (NAME=+val). Whitespace around entries is ignored. Values may include environment variable references (e.g. $HOME or ${HOME}), which will be expanded before applying the assignment.

Current implementation notes: apply uses expand to expand the RHS values and then applies the parsed operations. The working copy env_ is updated so later calls can observe previous changes.

applyOperation()

void applyOperation	(	const std::string &	name,
		Operation	op,
		const std::string &	val )

expand()

std::string expand ( const std::string & input )

static

Return the expanded form of the comma-separated assignment list without modifying the process environment.

This mirrors the expansions performed by apply.

Special behavior: append and prepend operations are returned as explicit replacement assignments combining the existing environment value and the expanded RHS. For example, if the current value of PATH is "/usr/bin" and the input contains "PATH+=/opt/bin", this method returns "PATH=/usr/bin:/opt/bin" (or "PATH=/opt/bin" if PATH was not previously set).

expandVariables()

std::string expandVariables ( const std::string & value )

static

splitAssignments()

std::vector< std::string > splitAssignments ( const std::string & input )

static

splitOperation()

std::tuple< std::string, EnvExpander::Operation, std::string > splitOperation ( const std::string & assignment )

static

Member Data Documentation

env_

boost::process::environment env_

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

• ArmarXCore/core/system/EnvExpander.h
• ArmarXCore/core/system/EnvExpander.cpp