Fundamental library of the Clojure language
Fundamental library of the Clojure language
Facilities for async programming and communication.
go blocks are dispatched over an internal thread pool, which
defaults to 8 threads. The size of this pool can be modified using
the Java system property clojure.core.async.pool-size
.
Facilities for async programming and communication. go blocks are dispatched over an internal thread pool, which defaults to 8 threads. The size of this pool can be modified using the Java system property `clojure.core.async.pool-size`.
No vars found in this namespace.
core.async HIGHLY EXPERIMENTAL feature exploration
Caveats:
Everything defined in this namespace is experimental, and subject to change or deletion without warning.
Many features provided by this namespace are highly coupled to implementation details of core.async. Potential features which operate at higher levels of abstraction are suitable for inclusion in the examples.
Features provided by this namespace MAY be promoted to clojure.core.async at a later point in time, but there is no guarantee any of them will.
core.async HIGHLY EXPERIMENTAL feature exploration Caveats: 1. Everything defined in this namespace is experimental, and subject to change or deletion without warning. 2. Many features provided by this namespace are highly coupled to implementation details of core.async. Potential features which operate at higher levels of abstraction are suitable for inclusion in the examples. 3. Features provided by this namespace MAY be promoted to clojure.core.async at a later point in time, but there is no guarantee any of them will.
A caching library for Clojure.
A caching library for Clojure.
core.memoize is a memoization library offering functionality above Clojure's core memoize
function in the following ways:
Pluggable memoization
core.memoize allows for different back-end cache implmentations to be used as appropriate without changing the memoization modus operandi.
Manipulable memoization
Because core.memoize allows you to access a function's memoization store, you do interesting things like clear it, modify it, and save it for later.
core.memoize is a memoization library offering functionality above Clojure's core `memoize` function in the following ways: **Pluggable memoization** core.memoize allows for different back-end cache implmentations to be used as appropriate without changing the memoization modus operandi. **Manipulable memoization** Because core.memoize allows you to access a function's memoization store, you do interesting things like clear it, modify it, and save it for later.
A library for reduction and parallel folding. Alpha and subject to change. Note that fold and its derivatives require Java 7+ or Java 6 + jsr166y.jar for fork/join support. See Clojure's pom.xml for the dependency info.
A library for reduction and parallel folding. Alpha and subject to change. Note that fold and its derivatives require Java 7+ or Java 6 + jsr166y.jar for fork/join support. See Clojure's pom.xml for the dependency info.
Socket server support
Socket server support
No vars found in this namespace.
Non-core data functions.
Non-core data functions.
A priority map is very similar to a sorted map, but whereas a sorted map produces a sequence of the entries sorted by key, a priority map produces the entries sorted by value. In addition to supporting all the functions a sorted map supports, a priority map can also be thought of as a queue of [item priority] pairs. To support usage as a versatile priority queue, priority maps also support conj/peek/pop operations.
The standard way to construct a priority map is with priority-map: user=> (def p (priority-map :a 2 :b 1 :c 3 :d 5 :e 4 :f 3)) #'user/p user=> p {:b 1, :a 2, :c 3, :f 3, :e 4, :d 5}
So :b has priority 1, :a has priority 2, and so on. Notice how the priority map prints in an order sorted by its priorities (i.e., the map's values)
We can use assoc to assign a priority to a new item: user=> (assoc p :g 1) {:b 1, :g 1, :a 2, :c 3, :f 3, :e 4, :d 5}
or to assign a new priority to an extant item: user=> (assoc p :c 4) {:b 1, :a 2, :f 3, :c 4, :e 4, :d 5}
We can remove an item from the priority map: user=> (dissoc p :e) {:b 1, :a 2, :c 3, :f 3, :d 5}
An alternative way to add to the priority map is to conj a [item priority] pair: user=> (conj p [:g 0]) {:g 0, :b 1, :a 2, :c 3, :f 3, :e 4, :d 5}
or use into: user=> (into p [[:g 0] [:h 1] [:i 2]]) {:g 0, :b 1, :h 1, :a 2, :i 2, :c 3, :f 3, :e 4, :d 5}
Priority maps are countable: user=> (count p) 6
Like other maps, equivalence is based not on type, but on contents. In other words, just as a sorted-map can be equal to a hash-map, so can a priority-map. user=> (= p {:b 1, :a 2, :c 3, :f 3, :e 4, :d 5}) true
You can test them for emptiness: user=> (empty? (priority-map)) true user=> (empty? p) false
You can test whether an item is in the priority map: user=> (contains? p :a) true user=> (contains? p :g) false
It is easy to look up the priority of a given item, using any of the standard map mechanisms: user=> (get p :a) 2 user=> (get p :g 10) 10 user=> (p :a) 2 user=> (:a p) 2
Priority maps derive much of their utility by providing priority-based seq. Note that no guarantees are made about the order in which items of the same priority appear. user=> (seq p) ([:b 1] [:a 2] [:c 3] [:f 3] [:e 4] [:d 5]) Because no guarantees are made about the order of same-priority items, note that rseq might not be an exact reverse of the seq. It is only guaranteed to be in descending order. user=> (rseq p) ([:d 5] [:e 4] [:c 3] [:f 3] [:a 2] [:b 1])
This means first/rest/next/for/map/etc. all operate in priority order. user=> (first p) [:b 1] user=> (rest p) ([:a 2] [:c 3] [:f 3] [:e 4] [:d 5])
Priority maps support metadata: user=> (meta (with-meta p {:extra :info})) {:extra :info}
But perhaps most importantly, priority maps can also function as priority queues. peek, like first, gives you the first [item priority] pair in the collection. pop removes the first [item priority] from the collection. (Note that unlike rest, which returns a seq, pop returns a priority map).
user=> (peek p) [:b 1] user=> (pop p) {:a 2, :c 3, :f 3, :e 4, :d 5}
It is also possible to use a custom comparator: user=> (priority-map-by > :a 1 :b 2 :c 3) {:c 3, :b 2, :a 1}
Sometimes, it is desirable to have a map where the values contain more information than just the priority. For example, let's say you want a map like: {:a [2 :apple], :b [1 :banana], :c [3 :carrot]} and you want to sort the map by the numeric priority found in the pair.
A common mistake is to try to solve this with a custom comparator: (priority-map (fn [[priority1 _] [priority2 _]] (< priority1 priority2)) :a [2 :apple], :b [1 :banana], :c [3 :carrot])
This will not work! In Clojure, like Java, all comparators must be total orders, meaning that you can't have a tie unless the objects you are comparing are in fact equal. The above comparator breaks that rule because [2 :apple] and [2 :apricot] tie, but are not equal.
The correct way to construct such a priority map is by specifying a keyfn, which is used
to extract the true priority from the priority map's vals. (Note: It might seem a little odd
that the priority-extraction function is called a keyfn, even though it is applied to the
map's values. This terminology is based on the docstring of clojure.core/sort-by, which
uses keyfn
for the function which extracts the sort order.)
In the above example,
user=> (priority-map-keyfn first :a [2 :apple], :b [1 :banana], :c [3 :carrot]) {:b [1 :banana], :a [2 :apple], :c [3 :carrot]}
You can also combine a keyfn with a comparator that operates on the extracted priorities:
user=> (priority-map-keyfn-by first > :a [2 :apple], :b [1 :banana], :c [3 :carrot]) {:c [3 :carrot], :a [2 :apple], :b [1 :banana]}
All of these operations are efficient. Generally speaking, most operations are O(log n) where n is the number of distinct priorities. Some operations (for example, straightforward lookup of an item's priority, or testing whether a given item is in the priority map) are as efficient as Clojure's built-in map.
The key to this efficiency is that internally, not only does the priority map store an ordinary hash map of items to priority, but it also stores a sorted map that maps priorities to sets of items with that priority.
A typical textbook priority queue data structure supports at the ability to add a [item priority] pair to the queue, and to pop/peek the next [item priority] pair. But many real-world applications of priority queues require more features, such as the ability to test whether something is already in the queue, or to reassign a priority. For example, a standard formulation of Dijkstra's algorithm requires the ability to reduce the priority number associated with a given item. Once you throw persistence into the mix with the desire to adjust priorities, the traditional structures just don't work that well.
This particular blend of Clojure's built-in hash sets, hash maps, and sorted maps proved to be a great way to implement an especially flexible persistent priority queue.
Connoisseurs of algorithms will note that this structure's peek operation is not O(1) as it would be if based upon a heap data structure, but I feel this is a small concession for the blend of persistence, priority reassignment, and priority-sorted seq, which can be quite expensive to achieve with a heap (I did actually try this for comparison). Furthermore, this peek's logarithmic behavior is quite good (on my computer I can do a million peeks at a priority map with a million items in 750ms). Also, consider that peek and pop usually follow one another, and even with a heap, pop is logarithmic. So the net combination of peek and pop is not much different between this versatile formulation of a priority map and a more limited heap-based one. In a nutshell, peek, although not O(1), is unlikely to be the bottleneck in your program.
All in all, I hope you will find priority maps to be an easy-to-use and useful addition to Clojure's assortment of built-in maps (hash-map and sorted-map).
A priority map is very similar to a sorted map, but whereas a sorted map produces a sequence of the entries sorted by key, a priority map produces the entries sorted by value. In addition to supporting all the functions a sorted map supports, a priority map can also be thought of as a queue of [item priority] pairs. To support usage as a versatile priority queue, priority maps also support conj/peek/pop operations. The standard way to construct a priority map is with priority-map: user=> (def p (priority-map :a 2 :b 1 :c 3 :d 5 :e 4 :f 3)) #'user/p user=> p {:b 1, :a 2, :c 3, :f 3, :e 4, :d 5} So :b has priority 1, :a has priority 2, and so on. Notice how the priority map prints in an order sorted by its priorities (i.e., the map's values) We can use assoc to assign a priority to a new item: user=> (assoc p :g 1) {:b 1, :g 1, :a 2, :c 3, :f 3, :e 4, :d 5} or to assign a new priority to an extant item: user=> (assoc p :c 4) {:b 1, :a 2, :f 3, :c 4, :e 4, :d 5} We can remove an item from the priority map: user=> (dissoc p :e) {:b 1, :a 2, :c 3, :f 3, :d 5} An alternative way to add to the priority map is to conj a [item priority] pair: user=> (conj p [:g 0]) {:g 0, :b 1, :a 2, :c 3, :f 3, :e 4, :d 5} or use into: user=> (into p [[:g 0] [:h 1] [:i 2]]) {:g 0, :b 1, :h 1, :a 2, :i 2, :c 3, :f 3, :e 4, :d 5} Priority maps are countable: user=> (count p) 6 Like other maps, equivalence is based not on type, but on contents. In other words, just as a sorted-map can be equal to a hash-map, so can a priority-map. user=> (= p {:b 1, :a 2, :c 3, :f 3, :e 4, :d 5}) true You can test them for emptiness: user=> (empty? (priority-map)) true user=> (empty? p) false You can test whether an item is in the priority map: user=> (contains? p :a) true user=> (contains? p :g) false It is easy to look up the priority of a given item, using any of the standard map mechanisms: user=> (get p :a) 2 user=> (get p :g 10) 10 user=> (p :a) 2 user=> (:a p) 2 Priority maps derive much of their utility by providing priority-based seq. Note that no guarantees are made about the order in which items of the same priority appear. user=> (seq p) ([:b 1] [:a 2] [:c 3] [:f 3] [:e 4] [:d 5]) Because no guarantees are made about the order of same-priority items, note that rseq might not be an exact reverse of the seq. It is only guaranteed to be in descending order. user=> (rseq p) ([:d 5] [:e 4] [:c 3] [:f 3] [:a 2] [:b 1]) This means first/rest/next/for/map/etc. all operate in priority order. user=> (first p) [:b 1] user=> (rest p) ([:a 2] [:c 3] [:f 3] [:e 4] [:d 5]) Priority maps support metadata: user=> (meta (with-meta p {:extra :info})) {:extra :info} But perhaps most importantly, priority maps can also function as priority queues. peek, like first, gives you the first [item priority] pair in the collection. pop removes the first [item priority] from the collection. (Note that unlike rest, which returns a seq, pop returns a priority map). user=> (peek p) [:b 1] user=> (pop p) {:a 2, :c 3, :f 3, :e 4, :d 5} It is also possible to use a custom comparator: user=> (priority-map-by > :a 1 :b 2 :c 3) {:c 3, :b 2, :a 1} Sometimes, it is desirable to have a map where the values contain more information than just the priority. For example, let's say you want a map like: {:a [2 :apple], :b [1 :banana], :c [3 :carrot]} and you want to sort the map by the numeric priority found in the pair. A common mistake is to try to solve this with a custom comparator: (priority-map (fn [[priority1 _] [priority2 _]] (< priority1 priority2)) :a [2 :apple], :b [1 :banana], :c [3 :carrot]) This will not work! In Clojure, like Java, all comparators must be total orders, meaning that you can't have a tie unless the objects you are comparing are in fact equal. The above comparator breaks that rule because [2 :apple] and [2 :apricot] tie, but are not equal. The correct way to construct such a priority map is by specifying a keyfn, which is used to extract the true priority from the priority map's vals. (Note: It might seem a little odd that the priority-extraction function is called a *key*fn, even though it is applied to the map's values. This terminology is based on the docstring of clojure.core/sort-by, which uses `keyfn` for the function which extracts the sort order.) In the above example, user=> (priority-map-keyfn first :a [2 :apple], :b [1 :banana], :c [3 :carrot]) {:b [1 :banana], :a [2 :apple], :c [3 :carrot]} You can also combine a keyfn with a comparator that operates on the extracted priorities: user=> (priority-map-keyfn-by first > :a [2 :apple], :b [1 :banana], :c [3 :carrot]) {:c [3 :carrot], :a [2 :apple], :b [1 :banana]} All of these operations are efficient. Generally speaking, most operations are O(log n) where n is the number of distinct priorities. Some operations (for example, straightforward lookup of an item's priority, or testing whether a given item is in the priority map) are as efficient as Clojure's built-in map. The key to this efficiency is that internally, not only does the priority map store an ordinary hash map of items to priority, but it also stores a sorted map that maps priorities to sets of items with that priority. A typical textbook priority queue data structure supports at the ability to add a [item priority] pair to the queue, and to pop/peek the next [item priority] pair. But many real-world applications of priority queues require more features, such as the ability to test whether something is already in the queue, or to reassign a priority. For example, a standard formulation of Dijkstra's algorithm requires the ability to reduce the priority number associated with a given item. Once you throw persistence into the mix with the desire to adjust priorities, the traditional structures just don't work that well. This particular blend of Clojure's built-in hash sets, hash maps, and sorted maps proved to be a great way to implement an especially flexible persistent priority queue. Connoisseurs of algorithms will note that this structure's peek operation is not O(1) as it would be if based upon a heap data structure, but I feel this is a small concession for the blend of persistence, priority reassignment, and priority-sorted seq, which can be quite expensive to achieve with a heap (I did actually try this for comparison). Furthermore, this peek's logarithmic behavior is quite good (on my computer I can do a million peeks at a priority map with a million items in 750ms). Also, consider that peek and pop usually follow one another, and even with a heap, pop is logarithmic. So the net combination of peek and pop is not much different between this versatile formulation of a priority map and a more limited heap-based one. In a nutshell, peek, although not O(1), is unlikely to be the bottleneck in your program. All in all, I hope you will find priority maps to be an easy-to-use and useful addition to Clojure's assortment of built-in maps (hash-map and sorted-map).
Graphical object inspector for Clojure data structures.
Graphical object inspector for Clojure data structures.
Start a web browser from Clojure
Start a web browser from Clojure
Helper namespace for clojure.java.browse. Prevents console apps from becoming GUI unnecessarily.
Helper namespace for clojure.java.browse. Prevents console apps from becoming GUI unnecessarily.
No vars found in this namespace.
This file defines polymorphic I/O utility functions for Clojure.
This file defines polymorphic I/O utility functions for Clojure.
A repl helper to quickly open javadocs.
A repl helper to quickly open javadocs.
Conveniently launch a sub-process providing its stdin and collecting its stdout
Conveniently launch a sub-process providing its stdin and collecting its stdout
Top-level main function for Clojure REPL and scripts.
Top-level main function for Clojure REPL and scripts.
A Pretty Printer for Clojure
clojure.pprint implements a flexible system for printing structured data in a pleasing, easy-to-understand format. Basic use of the pretty printer is simple, just call pprint instead of println. More advanced users can use the building blocks provided to create custom output formats.
Out of the box, pprint supports a simple structured format for basic data and a specialized format for Clojure source code. More advanced formats, including formats that don't look like Clojure data at all like XML and JSON, can be rendered by creating custom dispatch functions.
In addition to the pprint function, this module contains cl-format, a text formatting function which is fully compatible with the format function in Common Lisp. Because pretty printing directives are directly integrated with cl-format, it supports very concise custom dispatch. It also provides a more powerful alternative to Clojure's standard format function.
See documentation for pprint and cl-format for more information or complete documentation on the Clojure web site on GitHub.
A Pretty Printer for Clojure clojure.pprint implements a flexible system for printing structured data in a pleasing, easy-to-understand format. Basic use of the pretty printer is simple, just call pprint instead of println. More advanced users can use the building blocks provided to create custom output formats. Out of the box, pprint supports a simple structured format for basic data and a specialized format for Clojure source code. More advanced formats, including formats that don't look like Clojure data at all like XML and JSON, can be rendered by creating custom dispatch functions. In addition to the pprint function, this module contains cl-format, a text formatting function which is fully compatible with the format function in Common Lisp. Because pretty printing directives are directly integrated with cl-format, it supports very concise custom dispatch. It also provides a more powerful alternative to Clojure's standard format function. See documentation for pprint and cl-format for more information or complete documentation on the Clojure web site on GitHub.
Reflection on Host Types Alpha - subject to change.
Two main entry points:
Key features:
Exposes the read side of reflection as pure data. Reflecting on a type returns a map with keys :bases, :flags, and :members.
Canonicalizes class names as Clojure symbols. Types can extend to the TypeReference protocol to indicate that they can be unambiguously resolved as a type name. The canonical format requires one non-Java-ish convention: array brackets are <> instead of [] so they can be part of a Clojure symbol.
Pluggable Reflectors for different implementations. The default JavaReflector is good when you have a class in hand, or use the AsmReflector for "hands off" reflection without forcing classes to load.
Platform implementers must:
Reflection on Host Types Alpha - subject to change. Two main entry points: * type-reflect reflects on something that implements TypeReference. * reflect (for REPL use) reflects on the class of an instance, or on a class if passed a class Key features: * Exposes the read side of reflection as pure data. Reflecting on a type returns a map with keys :bases, :flags, and :members. * Canonicalizes class names as Clojure symbols. Types can extend to the TypeReference protocol to indicate that they can be unambiguously resolved as a type name. The canonical format requires one non-Java-ish convention: array brackets are <> instead of [] so they can be part of a Clojure symbol. * Pluggable Reflectors for different implementations. The default JavaReflector is good when you have a class in hand, or use the AsmReflector for "hands off" reflection without forcing classes to load. Platform implementers must: * Create an implementation of Reflector. * Create one or more implementations of TypeReference. * def default-reflector to be an instance that satisfies Reflector.
Utilities meant to be used interactively at the REPL
Utilities meant to be used interactively at the REPL
Set operations such as union/intersection.
Set operations such as union/intersection.
Print stack traces oriented towards Clojure, not Java.
Print stack traces oriented towards Clojure, not Java.
Clojure String utilities
It is poor form to (:use clojure.string). Instead, use require with :as to specify a prefix, e.g.
(ns your.namespace.here (:require [clojure.string :as str]))
Design notes for clojure.string:
Strings are objects (as opposed to sequences). As such, the string being manipulated is the first argument to a function; passing nil will result in a NullPointerException unless documented otherwise. If you want sequence-y behavior instead, use a sequence.
Functions are generally not lazy, and call straight to host methods where those are available and efficient.
Functions take advantage of String implementation details to write high-performing loop/recurs instead of using higher-order functions. (This is not idiomatic in general-purpose application code.)
When a function is documented to accept a string argument, it will take any implementation of the correct interface on the host platform. In Java, this is CharSequence, which is more general than String. In ordinary usage you will almost always pass concrete strings. If you are doing something unusual, e.g. passing a mutable implementation of CharSequence, then thread-safety is your responsibility.
Clojure String utilities It is poor form to (:use clojure.string). Instead, use require with :as to specify a prefix, e.g. (ns your.namespace.here (:require [clojure.string :as str])) Design notes for clojure.string: 1. Strings are objects (as opposed to sequences). As such, the string being manipulated is the first argument to a function; passing nil will result in a NullPointerException unless documented otherwise. If you want sequence-y behavior instead, use a sequence. 2. Functions are generally not lazy, and call straight to host methods where those are available and efficient. 3. Functions take advantage of String implementation details to write high-performing loop/recurs instead of using higher-order functions. (This is not idiomatic in general-purpose application code.) 4. When a function is documented to accept a string argument, it will take any implementation of the correct *interface* on the host platform. In Java, this is CharSequence, which is more general than String. In ordinary usage you will almost always pass concrete strings. If you are doing something unusual, e.g. passing a mutable implementation of CharSequence, then thread-safety is your responsibility.
Macros that expand to repeated copies of a template expression.
Macros that expand to repeated copies of a template expression.
A unit testing framework.
ASSERTIONS
The core of the library is the "is" macro, which lets you make assertions of any arbitrary expression:
(is (= 4 (+ 2 2))) (is (instance? Integer 256)) (is (.startsWith "abcde" "ab"))
You can type an "is" expression directly at the REPL, which will print a message if it fails.
user> (is (= 5 (+ 2 2)))
FAIL in (:1)
expected: (= 5 (+ 2 2))
actual: (not (= 5 4))
false
The "expected:" line shows you the original expression, and the "actual:" shows you what actually happened. In this case, it shows that (+ 2 2) returned 4, which is not = to 5. Finally, the "false" on the last line is the value returned from the expression. The "is" macro always returns the result of the inner expression.
There are two special assertions for testing exceptions. The "(is (thrown? c ...))" form tests if an exception of class c is thrown:
(is (thrown? ArithmeticException (/ 1 0)))
"(is (thrown-with-msg? c re ...))" does the same thing and also tests that the message on the exception matches the regular expression re:
(is (thrown-with-msg? ArithmeticException #"Divide by zero" (/ 1 0)))
DOCUMENTING TESTS
"is" takes an optional second argument, a string describing the assertion. This message will be included in the error report.
(is (= 5 (+ 2 2)) "Crazy arithmetic")
In addition, you can document groups of assertions with the "testing" macro, which takes a string followed by any number of assertions. The string will be included in failure reports. Calls to "testing" may be nested, and all of the strings will be joined together with spaces in the final report, in a style similar to RSpec http://rspec.info/
(testing "Arithmetic" (testing "with positive integers" (is (= 4 (+ 2 2))) (is (= 7 (+ 3 4)))) (testing "with negative integers" (is (= -4 (+ -2 -2))) (is (= -1 (+ 3 -4)))))
Note that, unlike RSpec, the "testing" macro may only be used INSIDE a "deftest" or "with-test" form (see below).
DEFINING TESTS
There are two ways to define tests. The "with-test" macro takes a defn or def form as its first argument, followed by any number of assertions. The tests will be stored as metadata on the definition.
(with-test (defn my-function [x y] (+ x y)) (is (= 4 (my-function 2 2))) (is (= 7 (my-function 3 4))))
As of Clojure SVN rev. 1221, this does not work with defmacro. See http://code.google.com/p/clojure/issues/detail?id=51
The other way lets you define tests separately from the rest of your code, even in a different namespace:
(deftest addition (is (= 4 (+ 2 2))) (is (= 7 (+ 3 4))))
(deftest subtraction (is (= 1 (- 4 3))) (is (= 3 (- 7 4))))
This creates functions named "addition" and "subtraction", which can be called like any other function. Therefore, tests can be grouped and composed, in a style similar to the test framework in Peter Seibel's "Practical Common Lisp" http://www.gigamonkeys.com/book/practical-building-a-unit-test-framework.html
(deftest arithmetic (addition) (subtraction))
The names of the nested tests will be joined in a list, like "(arithmetic addition)", in failure reports. You can use nested tests to set up a context shared by several tests.
RUNNING TESTS
Run tests with the function "(run-tests namespaces...)":
(run-tests 'your.namespace 'some.other.namespace)
If you don't specify any namespaces, the current namespace is used. To run all tests in all namespaces, use "(run-all-tests)".
By default, these functions will search for all tests defined in a namespace and run them in an undefined order. However, if you are composing tests, as in the "arithmetic" example above, you probably do not want the "addition" and "subtraction" tests run separately. In that case, you must define a special function named "test-ns-hook" that runs your tests in the correct order:
(defn test-ns-hook [] (arithmetic))
Note: test-ns-hook prevents execution of fixtures (see below).
OMITTING TESTS FROM PRODUCTION CODE
You can bind the variable "load-tests" to false when loading or compiling code in production. This will prevent any tests from being created by "with-test" or "deftest".
FIXTURES
Fixtures allow you to run code before and after tests, to set up the context in which tests should be run.
A fixture is just a function that calls another function passed as an argument. It looks like this:
(defn my-fixture [f] Perform setup, establish bindings, whatever. (f) Then call the function we were passed. Tear-down / clean-up code here. )
Fixtures are attached to namespaces in one of two ways. "each" fixtures are run repeatedly, once for each test function created with "deftest" or "with-test". "each" fixtures are useful for establishing a consistent before/after state for each test, like clearing out database tables.
"each" fixtures can be attached to the current namespace like this: (use-fixtures :each fixture1 fixture2 ...) The fixture1, fixture2 are just functions like the example above. They can also be anonymous functions, like this: (use-fixtures :each (fn [f] setup... (f) cleanup...))
The other kind of fixture, a "once" fixture, is only run once, around ALL the tests in the namespace. "once" fixtures are useful for tasks that only need to be performed once, like establishing database connections, or for time-consuming tasks.
Attach "once" fixtures to the current namespace like this: (use-fixtures :once fixture1 fixture2 ...)
Note: Fixtures and test-ns-hook are mutually incompatible. If you are using test-ns-hook, fixture functions will never be run.
SAVING TEST OUTPUT TO A FILE
All the test reporting functions write to the var test-out. By default, this is the same as out, but you can rebind it to any PrintWriter. For example, it could be a file opened with clojure.java.io/writer.
EXTENDING TEST-IS (ADVANCED)
You can extend the behavior of the "is" macro by defining new methods for the "assert-expr" multimethod. These methods are called during expansion of the "is" macro, so they should return quoted forms to be evaluated.
You can plug in your own test-reporting framework by rebinding the "report" function: (report event)
The 'event' argument is a map. It will always have a :type key, whose value will be a keyword signaling the type of event being reported. Standard events with :type value of :pass, :fail, and :error are called when an assertion passes, fails, and throws an exception, respectively. In that case, the event will also have the following keys:
:expected The form that was expected to be true :actual A form representing what actually occurred :message The string message given as an argument to 'is'
The "testing" strings will be a list in "testing-contexts", and the vars being tested will be a list in "testing-vars".
Your "report" function should wrap any printing calls in the "with-test-out" macro, which rebinds out to the current value of test-out.
For additional event types, see the examples in the code.
A unit testing framework. ASSERTIONS The core of the library is the "is" macro, which lets you make assertions of any arbitrary expression: (is (= 4 (+ 2 2))) (is (instance? Integer 256)) (is (.startsWith "abcde" "ab")) You can type an "is" expression directly at the REPL, which will print a message if it fails. user> (is (= 5 (+ 2 2))) FAIL in (:1) expected: (= 5 (+ 2 2)) actual: (not (= 5 4)) false The "expected:" line shows you the original expression, and the "actual:" shows you what actually happened. In this case, it shows that (+ 2 2) returned 4, which is not = to 5. Finally, the "false" on the last line is the value returned from the expression. The "is" macro always returns the result of the inner expression. There are two special assertions for testing exceptions. The "(is (thrown? c ...))" form tests if an exception of class c is thrown: (is (thrown? ArithmeticException (/ 1 0))) "(is (thrown-with-msg? c re ...))" does the same thing and also tests that the message on the exception matches the regular expression re: (is (thrown-with-msg? ArithmeticException #"Divide by zero" (/ 1 0))) DOCUMENTING TESTS "is" takes an optional second argument, a string describing the assertion. This message will be included in the error report. (is (= 5 (+ 2 2)) "Crazy arithmetic") In addition, you can document groups of assertions with the "testing" macro, which takes a string followed by any number of assertions. The string will be included in failure reports. Calls to "testing" may be nested, and all of the strings will be joined together with spaces in the final report, in a style similar to RSpec <http://rspec.info/> (testing "Arithmetic" (testing "with positive integers" (is (= 4 (+ 2 2))) (is (= 7 (+ 3 4)))) (testing "with negative integers" (is (= -4 (+ -2 -2))) (is (= -1 (+ 3 -4))))) Note that, unlike RSpec, the "testing" macro may only be used INSIDE a "deftest" or "with-test" form (see below). DEFINING TESTS There are two ways to define tests. The "with-test" macro takes a defn or def form as its first argument, followed by any number of assertions. The tests will be stored as metadata on the definition. (with-test (defn my-function [x y] (+ x y)) (is (= 4 (my-function 2 2))) (is (= 7 (my-function 3 4)))) As of Clojure SVN rev. 1221, this does not work with defmacro. See http://code.google.com/p/clojure/issues/detail?id=51 The other way lets you define tests separately from the rest of your code, even in a different namespace: (deftest addition (is (= 4 (+ 2 2))) (is (= 7 (+ 3 4)))) (deftest subtraction (is (= 1 (- 4 3))) (is (= 3 (- 7 4)))) This creates functions named "addition" and "subtraction", which can be called like any other function. Therefore, tests can be grouped and composed, in a style similar to the test framework in Peter Seibel's "Practical Common Lisp" <http://www.gigamonkeys.com/book/practical-building-a-unit-test-framework.html> (deftest arithmetic (addition) (subtraction)) The names of the nested tests will be joined in a list, like "(arithmetic addition)", in failure reports. You can use nested tests to set up a context shared by several tests. RUNNING TESTS Run tests with the function "(run-tests namespaces...)": (run-tests 'your.namespace 'some.other.namespace) If you don't specify any namespaces, the current namespace is used. To run all tests in all namespaces, use "(run-all-tests)". By default, these functions will search for all tests defined in a namespace and run them in an undefined order. However, if you are composing tests, as in the "arithmetic" example above, you probably do not want the "addition" and "subtraction" tests run separately. In that case, you must define a special function named "test-ns-hook" that runs your tests in the correct order: (defn test-ns-hook [] (arithmetic)) Note: test-ns-hook prevents execution of fixtures (see below). OMITTING TESTS FROM PRODUCTION CODE You can bind the variable "*load-tests*" to false when loading or compiling code in production. This will prevent any tests from being created by "with-test" or "deftest". FIXTURES Fixtures allow you to run code before and after tests, to set up the context in which tests should be run. A fixture is just a function that calls another function passed as an argument. It looks like this: (defn my-fixture [f] Perform setup, establish bindings, whatever. (f) Then call the function we were passed. Tear-down / clean-up code here. ) Fixtures are attached to namespaces in one of two ways. "each" fixtures are run repeatedly, once for each test function created with "deftest" or "with-test". "each" fixtures are useful for establishing a consistent before/after state for each test, like clearing out database tables. "each" fixtures can be attached to the current namespace like this: (use-fixtures :each fixture1 fixture2 ...) The fixture1, fixture2 are just functions like the example above. They can also be anonymous functions, like this: (use-fixtures :each (fn [f] setup... (f) cleanup...)) The other kind of fixture, a "once" fixture, is only run once, around ALL the tests in the namespace. "once" fixtures are useful for tasks that only need to be performed once, like establishing database connections, or for time-consuming tasks. Attach "once" fixtures to the current namespace like this: (use-fixtures :once fixture1 fixture2 ...) Note: Fixtures and test-ns-hook are mutually incompatible. If you are using test-ns-hook, fixture functions will *never* be run. SAVING TEST OUTPUT TO A FILE All the test reporting functions write to the var *test-out*. By default, this is the same as *out*, but you can rebind it to any PrintWriter. For example, it could be a file opened with clojure.java.io/writer. EXTENDING TEST-IS (ADVANCED) You can extend the behavior of the "is" macro by defining new methods for the "assert-expr" multimethod. These methods are called during expansion of the "is" macro, so they should return quoted forms to be evaluated. You can plug in your own test-reporting framework by rebinding the "report" function: (report event) The 'event' argument is a map. It will always have a :type key, whose value will be a keyword signaling the type of event being reported. Standard events with :type value of :pass, :fail, and :error are called when an assertion passes, fails, and throws an exception, respectively. In that case, the event will also have the following keys: :expected The form that was expected to be true :actual A form representing what actually occurred :message The string message given as an argument to 'is' The "testing" strings will be a list in "*testing-contexts*", and the vars being tested will be a list in "*testing-vars*". Your "report" function should wrap any printing calls in the "with-test-out" macro, which rebinds *out* to the current value of *test-out*. For additional event types, see the examples in the code.
clojure.test extension for JUnit-compatible XML output.
JUnit (http://junit.org/) is the most popular unit-testing library for Java. As such, tool support for JUnit output formats is common. By producing compatible output from tests, this tool support can be exploited.
To use, wrap any calls to clojure.test/run-tests in the with-junit-output macro, like this:
(use 'clojure.test) (use 'clojure.test.junit)
(with-junit-output (run-tests 'my.cool.library))
To write the output to a file, rebind clojure.test/test-out to your own PrintWriter (perhaps opened using clojure.java.io/writer).
clojure.test extension for JUnit-compatible XML output. JUnit (http://junit.org/) is the most popular unit-testing library for Java. As such, tool support for JUnit output formats is common. By producing compatible output from tests, this tool support can be exploited. To use, wrap any calls to clojure.test/run-tests in the with-junit-output macro, like this: (use 'clojure.test) (use 'clojure.test.junit) (with-junit-output (run-tests 'my.cool.library)) To write the output to a file, rebind clojure.test/*test-out* to your own PrintWriter (perhaps opened using clojure.java.io/writer).
clojure.test extensions for the Test Anything Protocol (TAP)
TAP is a simple text-based syntax for reporting test results. TAP was originally developed for Perl, and now has implementations in several languages. For more information on TAP, see http://testanything.org/ and http://search.cpan.org/~petdance/TAP-1.0.0/TAP.pm
To use this library, wrap any calls to clojure.test/run-tests in the with-tap-output macro, like this:
(use 'clojure.test) (use 'clojure.test.tap)
(with-tap-output (run-tests 'my.cool.library))
clojure.test extensions for the Test Anything Protocol (TAP) TAP is a simple text-based syntax for reporting test results. TAP was originally developed for Perl, and now has implementations in several languages. For more information on TAP, see http://testanything.org/ and http://search.cpan.org/~petdance/TAP-1.0.0/TAP.pm To use this library, wrap any calls to clojure.test/run-tests in the with-tap-output macro, like this: (use 'clojure.test) (use 'clojure.test.tap) (with-tap-output (run-tests 'my.cool.library))
Analyzer for clojure code, host agnostic.
Entry point:
Platform implementers must provide dynamic bindings for:
Setting up the global env is also required, see clojure.tools.analyzer.env
See clojure.tools.analyzer.core-test for an example on how to setup the analyzer.
Analyzer for clojure code, host agnostic. Entry point: * analyze Platform implementers must provide dynamic bindings for: * macroexpand-1 * parse * create-var * var? Setting up the global env is also required, see clojure.tools.analyzer.env See clojure.tools.analyzer.core-test for an example on how to setup the analyzer.
Utilities for AST walking/updating
Utilities for AST walking/updating
Utilities for querying tools.analyzer ASTs with Datomic
Utilities for querying tools.analyzer ASTs with Datomic
Analyzer for clojure code, extends tools.analyzer with JVM specific passes/forms
Analyzer for clojure code, extends tools.analyzer with JVM specific passes/forms
Utilities for pass scheduling
Utilities for pass scheduling
A clojure reader in clojure
A clojure reader in clojure
An EDN reader in clojure
An EDN reader in clojure
Protocols and default Reader types implementation
Protocols and default Reader types implementation
No vars found in this namespace.
This file defines a generic tree walker for Clojure data structures. It takes any data structure (list, vector, map, set, seq), calls a function on every element, and uses the return value of the function in place of the original. This makes it fairly easy to write recursive search-and-replace functions, as shown in the examples.
Note: "walk" supports all Clojure data structures EXCEPT maps created with sorted-map-by. There is no (obvious) way to retrieve the sorting function.
This file defines a generic tree walker for Clojure data structures. It takes any data structure (list, vector, map, set, seq), calls a function on every element, and uses the return value of the function in place of the original. This makes it fairly easy to write recursive search-and-replace functions, as shown in the examples. Note: "walk" supports all Clojure data structures EXCEPT maps created with sorted-map-by. There is no (obvious) way to retrieve the sorting function.
XML reading/writing.
XML reading/writing.
Functional hierarchical zipper, with navigation, editing, and enumeration. See Huet
Functional hierarchical zipper, with navigation, editing, and enumeration. See Huet
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