You can:

my $json = JSON->new;

print "Using JSON::XS\n" if $json->is_xs();

[download]

See the JSON choosing backend documentation and (further down in the documentation) the additional methods section for is_xx and related methods.

Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond

In reply to Re: How do I tell if my code is using JSON::PP or JSON::XS? by GrandFather
in thread How do I tell if my code is using JSON::PP or JSON::XS? by Cody Fendant

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