Skip to content

Commit 69afe91

Browse files
puredangerstuarthalloway
puredanger
authored and
stuarthalloway
committed
changelog updates for 1.7.0-alpha6
Signed-off-by: Stuart Halloway <[email protected]>
1 parent caa3b4f commit 69afe91

1 file changed

Lines changed: 145 additions & 6 deletions

File tree

‎changes.md‎

Lines changed: 145 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -51,7 +51,7 @@ transducers in different ways:
5151

5252
* sequence - takes a transformation and a coll and produces a lazy seq
5353
* transduce - reduce with a transformation (eager)
54-
* eduction - returns a reducible/seqable/iterable seq of applications of the transducer to items in coll. Applications are re-performed with every reduce/seq/iterator.
54+
* eduction - returns a reducible/iterable of applications of the transducer to items in coll. Applications are re-performed with every reduce/iterator.
5555
* run! - run the transformation for side effects on the collection
5656

5757
There have been a number of internal changes to support transducers:
@@ -69,8 +69,64 @@ Some related issues addressed during development:
6969
* [CLJ-1606](http://dev.clojure.org/jira/browse/CLJ-1606)
7070
* [CLJ-1621](http://dev.clojure.org/jira/browse/CLJ-1621)
7171
* [CLJ-1600](http://dev.clojure.org/jira/browse/CLJ-1600)
72+
* [CLJ-1635](http://dev.clojure.org/jira/browse/CLJ-1635)
73+
* [CLJ-1683](http://dev.clojure.org/jira/browse/CLJ-1683)
74+
* [CLJ-1669](http://dev.clojure.org/jira/browse/CLJ-1669)
7275

73-
### 1.2 Keyword and Symbol Construction
76+
### 1.2 Reader Conditionals
77+
78+
Reader Conditionals is a new capability to support portable code that
79+
can run on multiple Clojure platforms with only small changes. In
80+
particular, this feature aims to support the increasingly common case
81+
of libraries targeting both Clojure and ClojureScript.
82+
83+
Code intended to be common across multiple platforms should use a new
84+
supported file extension: ".cljc". When requested to load a namespace,
85+
the platform-specific file extension (.clj, .cljs) will be checked
86+
prior to .cljc.
87+
88+
A new reader form can be used to specify "reader conditional" code in
89+
cljc files (and *only* cljc files). Each platform defines a feature
90+
identifying the platform (:clj, :cljs, :cljr). The reader conditional
91+
specifies code that is read conditionally based on the feature/
92+
93+
Form #? takes a list of alternating feature and expression. These are
94+
checked like cond and the selected expression is read and returned. Other
95+
branches are unread. If no branch is selected, the reader reads nothing
96+
(not nil, but literally as if reading ""). An optional ":default" branch
97+
can be used as a fallthrough.
98+
99+
Reader conditional with 2 features and a default:
100+
101+
#?(:clj Double/NaN
102+
:cljs js/NaN
103+
:default nil)
104+
105+
There is also a reader conditional splicing form. The evaluated expression
106+
should be sequential and will be spliced into the surrounded code, similar
107+
to unqoute-splicing.
108+
109+
For example:
110+
111+
[1 2 #?@(:clj [3 4] :cljs [5 6])]
112+
113+
This form would read as [1 2 3 4] on Clojure, [1 2 5 6] on ClojureScript,
114+
and [1 2] on any other platform.
115+
116+
Additionally, the reader can now be invoked with options for the features
117+
to use and how to interpret reader conditionals. By default, reader conditionals
118+
are not allowed, but that can be turned on, or a "preserve" mode can be used to
119+
preserve all branches (most likely useful for tooling or source transforms).
120+
121+
In the preserve mode, the reader conditional itself and any tagged literals
122+
within the unselected branches are returned as tagged literal data.
123+
124+
For more information, see:
125+
http://dev.clojure.org/display/design/Reader+Conditionals
126+
127+
* [CLJ-1424](http://dev.clojure.org/jira/browse/CLJ-1424)
128+
129+
### 1.3 Keyword and Symbol Construction
74130

75131
In response to issues raised in [CLJ-1439](http://dev.clojure.org/jira/browse/CLJ-1439),
76132
several changes have been made in symbol and keyword construction:
@@ -82,7 +138,7 @@ in a performance increase.
82138
2) Keywords are cached and keyword construction includes a cache check. A change was made
83139
to only clear the cache reference queue when there is a cache miss.
84140

85-
### 1.3 Warn on Boxed Math
141+
### 1.4 Warn on Boxed Math
86142

87143
One source of performance issues is the (unintended) use of arithmetic operations on
88144
boxed numbers. To make detecting the presence of boxed math easier, a warning will now
@@ -104,8 +160,9 @@ Example use:
104160

105161
* [CLJ-1325](http://dev.clojure.org/jira/browse/CLJ-1325)
106162
* [CLJ-1535](http://dev.clojure.org/jira/browse/CLJ-1535)
163+
* [CLJ-1642](http://dev.clojure.org/jira/browse/CLJ-1642)
107164

108-
### 1.4 update - like update-in for first level
165+
### 1.5 update - like update-in for first level
109166

110167
`update` is a new function that is like update-in specifically for first-level keys:
111168

@@ -122,6 +179,65 @@ Example use:
122179

123180
* [CLJ-1251](http://dev.clojure.org/jira/browse/CLJ-1251)
124181

182+
### 1.6 Faster reduce and iterator paths
183+
184+
Several important Clojure functions now return sequences that also
185+
contain fast reduce() (or in some cases iterator()) paths. In many
186+
cases, the new implementations are also faster for lazy sequences
187+
188+
* repeat - now implements IReduce
189+
* cycle - implements IReduceInit
190+
* iterate - implements IReduceInit
191+
* range - implements IReduce, specialized case handles common case of all longs
192+
* keys - iterates directly over the keys of a map, without seq or MapEntry allocation
193+
* vals - iterates directly over the vals of a map, without seq or MapEntry allocation
194+
* iterator-seq - creates a chunked sequence when previously it was unchunked
195+
196+
Additionally, hash-maps and hash-sets now provide iterators that walk
197+
the data structure directly rather than via a sequence.
198+
199+
A new interface (IMapIterable) for direct key and val iterators on maps
200+
was added. External data structures can use this interface to provide
201+
direct key and val iterators via keys and vals.
202+
203+
These enhancements are particularly effective when used
204+
in tandem with transducers via transduce, sequence, into, and
205+
eduction.
206+
207+
* [CLJ-1603](http://dev.clojure.org/jira/browse/CLJ-1603)
208+
* [CLJ-1515](http://dev.clojure.org/jira/browse/CLJ-1515)
209+
* [CLJ-1602](http://dev.clojure.org/jira/browse/CLJ-1602)
210+
* [CLJ-1669](http://dev.clojure.org/jira/browse/CLJ-1669)
211+
212+
### 1.7 Printing as data
213+
214+
There have been enhancements in how the REPL prints values without a
215+
print-method, specifically Throwable and the fallthrough Object case.
216+
Both cases now print in a tagged literal data form that can be read
217+
by the reader.
218+
219+
Unhandled objects print with the class, hash code, and toString:
220+
221+
user=> *ns*
222+
#object[clojure.lang.Namespace 0x55aa628 "user"]
223+
224+
Thrown exceptions will still be printed in the normal way by the default
225+
REPL but printing them to a stream will show a different form:
226+
227+
user=> (/ 1 0)
228+
ArithmeticException Divide by zero clojure.lang.Numbers.divide (Numbers.java:158)
229+
user=> (println *e)
230+
#error{:cause Divide by zero,
231+
:via [{:type java.lang.ArithmeticException,
232+
:message Divide by zero,
233+
:at [clojure.lang.Numbers divide Numbers.java 158]}],
234+
:trace
235+
[[clojure.lang.Numbers divide Numbers.java 158]
236+
[clojure.lang.Numbers divide Numbers.java 3808]
237+
[user$eval5 invoke NO_SOURCE_FILE 3]
238+
;; elided ...
239+
]]}
240+
125241
## 2 Enhancements
126242

127243
### 2.1 Error messages
@@ -185,6 +301,14 @@ Example use:
185301
set now works with things that only implement Iterable or IReduceInit
186302
* [CLJ-1633](http://dev.clojure.org/jira/browse/CLJ-1633)
187303
PersistentList/creator doesn't handle ArraySeqs correctly
304+
* [CLJ-1589](http://dev.clojure.org/jira/browse/CLJ-1589)
305+
Clean up unused paths in InternalReduce
306+
* [CLJ-1677](http://dev.clojure.org/jira/browse/CLJ-1677)
307+
Add setLineNumber() to LineNumberingPushbackReader
308+
* [CLJ-1667](http://dev.clojure.org/jira/browse/CLJ-1667)
309+
Change test to avoid using hard-coded socket port
310+
* [CLJ-1683](http://dev.clojure.org/jira/browse/CLJ-1683)
311+
Change reduce tests to better catch reduce without init bugs
188312

189313
## 3 Bug Fixes
190314

@@ -224,8 +348,23 @@ Example use:
224348
Some IReduce/IReduceInit implementors don't respect reduced
225349
* [CLJ-979](http://dev.clojure.org/jira/browse/CLJ-979)
226350
Clojure resolves to wrong deftype classes when AOT compiling or reloading
227-
* [CLJ-1544](http://dev.clojure.org/jira/browse/CLJ-1544)
228-
AOT bug involving namespaces loaded before AOT compilation started
351+
* [CLJ-1636](http://dev.clojure.org/jira/browse/CLJ-1636)
352+
Fix intermittent SeqIterator problem by removing use of this as a sentinel
353+
* [CLJ-1637](http://dev.clojure.org/jira/browse/CLJ-1636)
354+
Fix regression from CLJ-1546 that broke vec on MapEntry
355+
* [CLJ-1663](http://dev.clojure.org/jira/browse/CLJ-1663)
356+
Fix regression from CLJ-979 for DynamicClassLoader classloader delegation
357+
* [CLJ-1604](http://dev.clojure.org/jira/browse/CLJ-1604)
358+
Fix error from AOT'ed code defining a var with a clojure.core symbol name
359+
* [CLJ-1561](http://dev.clojure.org/jira/browse/CLJ-1561)
360+
Fix incorrect line number reporting for error locations
361+
* [CLJ-1568](http://dev.clojure.org/jira/browse/CLJ-1568)
362+
Fix incorrect line number reporting for error locations
363+
* [CLJ-1638](http://dev.clojure.org/jira/browse/CLJ-1638)
364+
Fix regression from CLJ-1546 removed PersistentVector.create(List) method
365+
* [CLJ-1681](http://dev.clojure.org/jira/browse/CLJ-1681)
366+
Fix regression from CLJ-1248 (1.6) in reflection warning with literal nil argument
367+
229368

230369
# Changes to Clojure in Version 1.6
231370

0 commit comments

Comments
 (0)