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Make conj assoc dissoc and transient versions handle args similarly

Description

Examples that work as expected:

1 2 3 4 5 6 7 8 9 Clojure 1.7.0-master-SNAPSHOT user=> (dissoc {}) {} user=> (disj #{}) #{} user=> (conj {}) {} user=> (conj []) []

Examples that do not work as desired, but are changed by the proposed patch:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 user=> (assoc {}) ArityException Wrong number of args (1) passed to: core/assoc clojure.lang.AFn.throwArity (AFn.java:429) user=> (assoc! (transient {})) ArityException Wrong number of args (1) passed to: core/assoc! clojure.lang.AFn.throwArity (AFn.java:429) user=> (dissoc! (transient {})) ArityException Wrong number of args (1) passed to: core/dissoc! clojure.lang.AFn.throwArity (AFn.java:429) ;; patch enables conj! with multiple arguments, like conj user=> (conj! (transient []) 1 2 3) ArityException Wrong number of args (4) passed to: core/conj! clojure.lang.AFn.throwArity (AFn.java:429) ;; patch would give error for missing value for last key to assoc!, not silently use nil for last value user=> (assoc! (transient {}) 1 2 3) #object[clojure.lang.PersistentArrayMap$TransientArrayMap 0x2e7569b8 "clojure.lang.PersistentArrayMap$TransientArrayMap@2e7569b8"]

I looked through the rest of the code for similar cases, and found that there were some other differences between them in how different numbers of arguments were handled, such as:

+ conj handles an arbitrary number of arguments, but conj! does not.
+ assoc checks for a final key with no value specified (CLJ-1052), but assoc! did not.

History/discussion: A discussion came up in the Clojure Google group about conj giving an error when taking only a coll as an argument, as opposed to disj which works for this case:

https://groups.google.com/forum/?fromgroups=#!topic/clojure/Z9mFxsTYTqQ

Screened by: Alex Miller

Environment

None

Status

Assignee

Alex Miller

Reporter

Andy Fingerhut

Approval

Triaged

Patch

Code and Test

Affects versions

Release 1.5
Release 1.4
Release 1.6

Priority

Minor