I want to check whether a JSONPath in a corresponding file exists, independent of the type of value associated with it (i.e., a scalar, array, object). The following code is near to what I am l looking for.

I test whether the path's value is defined, which works fine except for the case that the value associated with the path is "null": The path obviously exists, but the program indicates that it is not existant:

#!/usr/bin/perl
use JSON::Path;

$json = q({ "key": "value", "object": { "elem1": "value1", "elem2": "v
+alue2" }, "array": [ 0, 1], "not_defined": null });
$json_path[0] = JSON::Path->new( "\$.key" );
$json_path[1] = JSON::Path->new( "\$.object" );
$json_path[2] = JSON::Path->new( "\$.non_exist" );
$json_path[3] = JSON::Path->new( "\$.array" );
$json_path[4] = JSON::Path->new( "\$.not_defined" );
for ( $i=0; $i<=$#json_path; $i++) {
print "Path $json_path[$i] ";
if ( defined $json_path[$i]->values( $json ) ) {
   print( "exists\n" ) ;
}
else {

   print( "does not exist\n" )

}

}

[download]

The output is:

Path $.key exists
Path $.object exists
Path $.non_exist does not exist
Path $.array exists
Path $.not_defined does not exist

[download]

How can I do this properly?

In reply to How to properly check a JSONPath for existance? by Bloehdian

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