NAME
Catmandu::Fix::add_field - add or change the value of a HASH key or ARRAY index
DESCRIPTION
Contrary to set_field, this will create the intermediate structures if they are missing.
SYNOPSIS
# Add a new field 'foo' with value '2'
add_field('foo','2');
# Change the value of 'foo' to 'bar 123'
add_field('foo','bar 123');
# Create a deeply nested key
add_field('my.deep.nested.key','hi');