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# frozen-string-literal: true
#
# The any_not_empty extension changes the behavior of Dataset#any?
# if called without a block. By default, this method uses the
# standard Enumerable behavior of enumerating results and seeing
# if any result is not false or nil. With this extension, it
# just checks whether the dataset is empty. This approach can
# be much faster if the dataset is currently large.
#
# DB[:table].any?
# # SELECT * FROM table
#
# DB[:table].extension(:any_not_empty).any?
# # SELECT 1 as one FROM table LIMIT 1
#
# You can load this extension into specific datasets:
#
# ds = DB[:table]
# ds = ds.extension(:any_not_empty)
#
# Or you can load it into all of a database's datasets, which
# is probably the desired behavior if you are using this extension:
#
# DB.extension(:any_not_empty)
#
# Note that this can result in any? returning a different result if
# the dataset has a row_proc that can return false or nil.
#
# Related module: Sequel::AnyNotEmpty
#
module Sequel
module AnyNotEmpty
# If a block is not given, return whether the dataset is not empty.
def any?
if defined?(yield)
super
else
!empty?
end
end
end
Dataset.register_extension(:any_not_empty, AnyNotEmpty)
end
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