This list is based on [aliases_spec.rb](https://raw.githubusercontent.com/rspec/rspec-expectations/6f975b08c996b1014654334229d5d4b020055690/spec/rspec/matchers/aliases_spec.rb).

You can see also [Module: RSpec::Matchers API](http://rubydoc.info/github/rspec/rspec-expectations/RSpec/Matchers).

|matcher|aliased to|description|
|:------|:---------|:----------|
|a_truthy_value|be_truthy|a truthy value|
|a_falsey_value|be_falsey|a falsey value|
|be_falsy|be_falsey|be falsy|
|a_falsy_value|be_falsey|a falsy value|
|a_nil_value|be_nil|a nil value|
|a_value > 3|be > 3|a value > 3|
|a_value < 3|be < 3|a value < 3|
|a_value <= 3|be <= 3|a value <= 3|
|a_value == 3|be == 3|a value == 3|
|a_value === 3|be === 3|a value === 3|
|an_instance_of(Integer)|be_an_instance_of(Integer)|an instance of Integer|
|a_kind_of(Integer)|be_a_kind_of(Integer)|a kind of Integer|
|a_value_between(1, 10)|be_between(1, 10)|a value between 1 and 10 (inclusive)|
|a_value_within(0.1).of(3)|be_within(0.1).of(3)|a value within 0.1 of 3|
|within(0.1).of(3)|be_within(0.1).of(3)|within 0.1 of 3|
|a_block_changing|change|a block changing result|
|changing|change|changing result|
|a_collection_containing_exactly(1, 2)|contain_exactly(1, 2)|a collection containing exactly 1 and 2|
|containing_exactly(1, 2)|contain_exactly(1, 2)|containing exactly 1 and 2|
|a_range_covering(1, 2)|cover(1, 2)|a range covering 1 and 2|
|covering(1, 2)|cover(1, 2)|covering 1 and 2|
|ending_with(23)|end_with(23)|ending with 23|
|a_collection_ending_with(23)|end_with(23)|a collection ending with 23|
|a_string_ending_with("z")|end_with("z")|a string ending with 'z'|
|an_object_eq_to(3)|eq 3|an object eq to 3|
|eq_to(3)|eq 3|eq to 3|
|an_object_eql_to(3)|eql 3|an object eql to 3|
|eql_to(3)|eql 3|eql to 3|
|an_object_equal_to(3)|equal 3|an object equal to 3|
|equal_to(3)|equal 3|equal to 3|
|an_object_existing|exist|an object existing|
|existing|exist|existing|
|an_object_having_attributes(:age => 32)|have_attributes(:age => 32)|an object having attributes {:age => 32}|
|a_string_including("a")|include("a")|a string including 'a'|
|a_collection_including("a")|include("a")|a collection including 'a'|
|a_hash_including(:a => 5)|include(:a => 5)|a hash including {:a => 5}|
|including(3)|include(3)|including 3|
|a_string_matching(/foo/)|match(/foo/)|a string matching /foo/|
|an_object_matching(/foo/)|match(/foo/)|an object matching /foo/|
|match_regex(/foo/)|match(/foo/)|match regex /foo/|
|matching(/foo/)|match(/foo/)|matching /foo/|
|a_block_outputting('foo').to_stdout|output('foo').to_stdout|a block outputting 'foo' to stdout|
|a_block_outputting('foo').to_stderr|output('foo').to_stderr|a block outputting 'foo' to stderr|
|a_block_raising(ArgumentError)|raise_error(ArgumentError)|a block raising ArgumentError|
|raising(ArgumentError)|raise_error(ArgumentError)|raising ArgumentError|
|an_object_responding_to(:foo)|respond_to(:foo)|an object responding to #foo|
|responding_to(:foo)|respond_to(:foo)|responding to #foo|
|an_object_satisfying { }|satisfy { }|an object satisfying block|
|satisfying { }|satisfy { }|satisfying block|
|a_collection_starting_with(23)|start_with(23)|a collection starting with 23|
|a_string_starting_with("z")|start_with("z")|a string starting with 'z'|
|starting_with("d")|start_with("d")|starting with 'd'|
|a_block_throwing(:foo)|throw_symbol(:foo)|a block throwing :foo|
|throwing(:foo)|throw_symbol(:foo)|throwing :foo|
|a_block_yielding_control|yield_control|a block yielding control|
|yielding_control|yield_control|yielding control|
|a_block_yielding_with_no_args|yield_with_no_args|a block yielding with no args|
|yielding_with_no_args|yield_with_no_args|yielding with no args|
|a_block_yielding_with_args|yield_with_args|a block yielding with args|
|yielding_with_args|yield_with_args|yielding with args|
|a_block_yielding_successive_args|yield_successive_args|a block yielding successive args()|
|yielding_successive_args|yield_successive_args|yielding successive args()|