read a file produced by a call to @dump (or @dumpvar) and set the value of the corresponding variables.

The basic use of is to recover values of global variables that have been previously saved with a @dump command. If the loaded variable is not defined at the calling point, a new global variable is implicitly defined by @loadvar. If the variable with the same name exist at the calling point, either global or local, this variable will be set with the saved value.

To be more precise, when @dump is called, the name of the variables in the arguments list are stored as well as the corresponding values in file. The variables in the argument list can be global or local variable.

When @loadvar is called, it is called in some scope sc. Each identifier in the dump file is searched in the current scope sc. If not found, the englobing scope is looked up, and the process is iterated until a variable is found or until reaching the global scope. If no global variable with the same identifier is found, a new global variable with this identifier is created. The value associated to the identifier is used to set the selected variable.

Beware that @loadvar does not trigger the whenever.

Nota Bene: because @loadvar can be called in a context which differs from the context of the call of @dump, there is no reason that the ’same’ variables will be set.

Here is an example:

       @global $a, $b, $c
       $a := 1
       $b := 2
       $c := 3
       $ret := @dump("/tmp/dump1", $a, $b, $c)
       $a := 0
       $b := 0
       $c := 0
       Group G1
          @local $b
          $b := 22
          Group G2
             @local $c
             $c := 33
             $ret := @loadvar("/tmp/dump1")
             print $a $b $c  ; print 1 2 3
          print $a $b $c
          ; print 1 2 0
          ; because the variable $c set by @loadvar is in G1
       print $a $b $c ; print 1 0 0

       $ret := @loadvar("/tmp/dump1")
       print $a $b $c ; print 1 2 3
In this example, the values of the global variables $a, $b and $c are saved by the @dump special form in file /tmp/dump1. The @loadvar is done in a context where a local variables $band $c hidde the global ones and these local variable (with global variable $a) will be affected by the @loadvar command.

See Data Exchange Functions: @dump    @dumpvar    @gnuplot    @json_read    @json_string    @json_write    @loadvalue    @loadvar    @nim2vezer    @parse    @plot    @read_file    @rplot    @savevalue    @set_osc_handling_double    @set_osc_handling_int64    @set_osc_handling_tab    @string2fun    @string2obj    @string2proc    @to_num    @xml_read    @xml_string