Values

All XPE values are tagged to indicate the type of value that they hold. (see types for a discussion on the types of values that can be stored and manipulated).

Simple access to XPE value

as an integer

as a float

as a string

Converting a basic C value to an XPE value

C integer to XPE integer

C float to XPE float

C string to XPE string

Coercion from a basic C value to an XPE value

C integer to XPE integer

C float to XPE float

C string to XPE string

Access to XPE value depending on type

Accessing an element from an XPE array value

as an integer element

as a float element

as a string element

as an XPE value element

as an XPE variable element

Accessing a member of an XPE structure value

as an integer member

as a float member

as a string member

as an XPE value member

as an XPE variable member

 

simple access to XPE value

given the XPE value xval is defined as:

	XPE::VALUE  xval

Then access will be:

• using xval as an integer

  	int	xint;
  
  	xint = xval.get_int();
  


 
• using xval as a float

  	float	xfloat;
  
  	xfloat = xval.get_float();
  


 
• using xval as a string

  	const char
  		*xstr;
  
  	xstr = xval.get_str();
  

 

converting a basic C value to an XPE value

given the XPE value xval is defined as:

	XPE::VALUE  xval

Then access will be:

• converting a C integer to an XPE integer

  	int	xint;
  
  	xint = 55;
  
  	xval = (long)xint;
  


 
• converting a C float to an XPE float

  	float	xfloat;
  
  	xfloat = 55.5
  
  	xval = xfloat;
  


 
• converting a C string to an XPE string

  	const char
  		*xstr;
  
  	xstr = "hello world";
  
  	xval = xstr;
  

 

coercion from a basic C value to an XPE value

• converting a C integer to an XPE integer

  	XPE::VALUE(55);
  


 
• converting a C float to an XPE float

  	XPE::VALUE(55.5);
  


 
• converting a C string to an XPE string

  	XPE::VALUE("hello world");
  

 

access to XPE value depending on type

given the XPE value xval is defined as:

	XPE::VALUE  xval

Then access will be:

	int	xint;

	float	xfloat;

	const char
		*xstr;


	switch (xval.get_type())
	{
	case XPE::VALUE_INT:
		// using xval as an integer
		xint = xval.get_int();
		printf("xval is an int (%d)\n", xint);
		break;

	case XPE::VALUE_FLOAT:
		// using xval as a float
		xfloat = xval.get_float();
		printf("xval is a float (%f)\n", xfloat)
		break;

	case XPE::VALUE_STR:
		// using xval as a string
		xstr = xval.get_str();
		printf("xval is a string (%s)\n", xstr);
		break;

	default:
		// do nothing
		printf("xval is of type %d\n", xval.get_type());
	}

 

accessing an element from an XPE array value

given the XPE value xval is defined as:

	XPE::VALUE  xval

Then access will be:

• using xval as an XPE array of integers

  	int	xint;
  
  	xint = xval.get_array().get_element(n1).get_int();
  


 
• using xval as an XPE array of floats

  	float	xfloat;
  
  	xfloat = xval.get_array().get_element(n1).get_float();
  


 
• using xval as an XPE array of strings

  	const char
  		*xstr;
  
  	xstr = xval.get_array().get_element(n1).get_str();
  


 
• using xval as an XPE array of XPE values

  	xval = xval.get_array().get_element(n1).get_xvalue();
  

  The value xval can now be further accessed again as an XPE value

 
 
• using xval as an XPE array of XPE variables

  	XPE::VARIABLE
  		xvar;
  
  	xvar = xval.get_array().get_element(n1);
  

  The variable xvar can now be further accessed as an XPE variable

 

accessing a member of an XPE structure value

given the XPE value xval is defined as:

	XPE::VALUE  xval

Then access will be:

• using xval as an XPE structure that has integer member 'jack'

  	int	xint;
  
  	xint = xval.get_struct().get_member("jack").get_int();
  


 
• using xval as an XPE structure that has float member 'jack'

  	float	xfloat;
  
  	xfloat = xval.get_struct().get_member("jack").get_float();
  


 
• using xval as an XPE structure that has string member 'jack'

  	const char
  		*xstr;
  
  	xstr = xval.get_struct().get_member("jack").get_str();
  


 
• using xval as an XPE structure that has an XPE value member 'jack'

  	xval = xval.get_struct().get_member("jack").get_xvalue();
  

  The value xval can now be further accessed again as an XPE value

 
 
• using xval as an XPE structure that has an XPE variable member 'jack'

  	XPE::VARIABLE
  		xvar;
  
  	xvar = xval.get_struct().get_member("jack");
  

  The variable xvar can now be further accessed as an XPE variable