Re: SRSLY? (= (true? identity) (false? identity)) => true

What might confuse you, is why Clojure even have true? and false? functions? Its because conditional constructs like if, cond, when, test for truthy (aka logical true) and falsey (aka logical false), not true and false. Nil and False are falsey, and everything else is truthy. Most of the time t

Re: SRSLY? (= (true? identity) (false? identity)) => true

(= 1 10) => false (= 2 10) => false (= 10 10) => true (= false false) => true (= (= 1 10) (= 2 10)) => true class BoolTest { public static void main(String args[]) { System.out.println(Boolean.TRUE.equals(System.class) == Boolean.FALSE.equals(System.class)); // prints "true", System.c

Re: SRSLY? (= (true? identity) (false? identity)) => true

By design, true? never throws an exception. Neither does false? You can create functions similar to those that throw an exception when given a non-boolean value, if you want such functions. (Note: examples below rely on existence of clojure.core/boolean? which does not exist in Clojure 1.8.0)

Re: SRSLY? (= (true? identity) (false? identity)) => true

Think about what you're asking: "Hey, is identity a boolean true value?" "No, it is a function, not a boolean" "Is, identity a boolean false value?" "No, it's a function, not a boolean" Makes plenty sense to me. On Fri, Sep 1, 2017 at 10:06 PM, Rostislav Svoboda < rostislav.svob...@gmail.c

Re: SRSLY? (= (true? identity) (false? identity)) => true

> identity isn't a boolean, so neither true? nor false? should return true for > it But then why it should return 'false'? 2017-09-02 6:04 GMT+02:00 Justin Smith : > identity isn't a boolean, so neither true? nor false? should return true for > it > > > On Fri, Sep 1, 2017 at 9:01 PM Rostislav S

Re: SRSLY? (= (true? identity) (false? identity)) => true

> You seem to be confused about what true? and false? are intended to do. No no, it's not me who's confused about booleans. It's the computer :) 2017-09-02 5:59 GMT+02:00 Justin Smith : > You seem to be confused about what true? and false? are intended to do. > > +user=> (doc true?) > ---

Re: SRSLY? (= (true? identity) (false? identity)) => true

identity isn't a boolean, so neither true? nor false? should return true for it On Fri, Sep 1, 2017 at 9:01 PM Rostislav Svoboda < rostislav.svob...@gmail.com> wrote: > > (true? identity) -> false > > (false? identity) -> false > > (= false false) -> true > > Well: > (= identity identity) -> tru

Re: SRSLY? (= (true? identity) (false? identity)) => true

> (true? identity) -> false > (false? identity) -> false > (= false false) -> true Well: (= identity identity) -> true My math books say booleans can't be true and false in the same time. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to th

Re: SRSLY? (= (true? identity) (false? identity)) => true

You seem to be confused about what true? and false? are intended to do. +user=> (doc true?) - clojure.core/true? ([x]) Returns true if x is the value true, false otherwise. nil +user=> (doc false?) - clojure.core/false? ([x]) Returns true if x is

Re: SRSLY? (= (true? identity) (false? identity)) => true

> This is what I would expect - the identity function is neither the value > true, or the value false Hmm. No matter what's the value of the identity, the functions 'true?', 'false?', 'not' should then return an exception (or something else) instead of a boolean. 2017-09-02 5:49 GMT+02:00 Mark E

Re: SRSLY? (= (true? identity) (false? identity)) => true

(true? identity) -> false (false? identity) -> false (= false false) -> true On Fri, Sep 1, 2017 at 8:43 PM, Rostislav Svoboda < rostislav.svob...@gmail.com> wrote: > Hi, can anybody explain it please? > > $ java -cp clojure-1.8.0.jar clojure.main > Clojure 1.8.0 > user=> (= (true? identity) (fal

Re: SRSLY? (= (true? identity) (false? identity)) => true

This is what I would expect - the identity function is neither the value true, or the value false On Fri, Sep 1, 2017 at 8:44 PM Rostislav Svoboda < rostislav.svob...@gmail.com> wrote: > Hi, can anybody explain it please? > > $ java -cp clojure-1.8.0.jar clojure.main > Clojure 1.8.0 > user=> (= (

Re: [ANN] Clojure 1.9.0-alpha19

Due to the new dependence on external jars, these instructions will be different in Clojure 1.9. We will be providing additional tooling to make this easier but that's still a work in progress. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post

SRSLY? (= (true? identity) (false? identity)) => true

Hi, can anybody explain it please? $ java -cp clojure-1.8.0.jar clojure.main Clojure 1.8.0 user=> (= (true? identity) (false? identity)) true And in 1.9.0-alpha19 it behaves the same. thx Bost -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post

Re: [ANN] Clojure 1.9.0-alpha19

Hi, readme.txt says: To run: java -cp clojure-${VERSION}.jar clojure.main so I tried it out: $ java -cp clojure-1.9.0-alpha19.jar clojure.main Exception in thread "main" java.lang.ExceptionInInitializerError at clojure.main.(main.java:20) Caused by: java.io.FileNotFoundException: Could not locat

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