Mixing
Combining “if-let” with “OR” so functions may be executed several times on one value
What I am trying to achieve is to execute functions on a value several times when several conditions are met. In particular say we have two variables a and b.
When a is true the value is transformed by the function associated to a, then
when b is true the new value is transformed by the function associated to b.
So when the initial value is 0 and the functions are inc and #(+ 5 %) we can get 0, 1, 5 or 6.
My approach was as following but not succeed
user> (def initial-number 0)
user> (if-let [a true b true] (cond-> initial-number a inc b (#(+ 5 %))))
IllegalArgumentException clojure.core/if-let requires exactly 2 forms in binding vector in user: clojure.core/if-let (core.clj:1758)
user>
if-statement clojure let
asked Jan 2 at 3:35
trzczytrzczy
344217
add a comment |
What I am trying to achieve is to execute functions on a value several times when several conditions are met. In particular say we have two variables a and b.
When a is true the value is transformed by the function associated to a, then
when b is true the new value is transformed by the function associated to b.
So when the initial value is 0 and the functions are inc and #(+ 5 %) we can get 0, 1, 5 or 6.
My approach was as following but not succeed
user> (def initial-number 0)
user> (if-let [a true b true] (cond-> initial-number a inc b (#(+ 5 %))))
IllegalArgumentException clojure.core/if-let requires exactly 2 forms in binding vector in user: clojure.core/if-let (core.clj:1758)
user>
if-statement clojure let
asked Jan 2 at 3:35
trzczytrzczy
344217
add a comment |
What I am trying to achieve is to execute functions on a value several times when several conditions are met. In particular say we have two variables a and b.
When a is true the value is transformed by the function associated to a, then
when b is true the new value is transformed by the function associated to b.
So when the initial value is 0 and the functions are inc and #(+ 5 %) we can get 0, 1, 5 or 6.
My approach was as following but not succeed
user> (def initial-number 0)
user> (if-let [a true b true] (cond-> initial-number a inc b (#(+ 5 %))))
IllegalArgumentException clojure.core/if-let requires exactly 2 forms in binding vector in user: clojure.core/if-let (core.clj:1758)
user>
if-statement clojure let
asked Jan 2 at 3:35
trzczytrzczy
344217
What I am trying to achieve is to execute functions on a value several times when several conditions are met. In particular say we have two variables a and b.
When a is true the value is transformed by the function associated to a, then
when b is true the new value is transformed by the function associated to b.
So when the initial value is 0 and the functions are inc and #(+ 5 %) we can get 0, 1, 5 or 6.
My approach was as following but not succeed
user> (def initial-number 0)
user> (if-let [a true b true] (cond-> initial-number a inc b (#(+ 5 %))))
IllegalArgumentException clojure.core/if-let requires exactly 2 forms in binding vector in user: clojure.core/if-let (core.clj:1758)
user>
if-statement clojure let
if-statement clojure let
asked Jan 2 at 3:35
trzczytrzczy
344217
asked Jan 2 at 3:35
trzczytrzczy
344217
asked Jan 2 at 3:35
trzczytrzczy
344217
asked Jan 2 at 3:35
trzczytrzczy
344217
asked Jan 2 at 3:35
trzczytrzczy
344217
344217
add a comment |
add a comment |
1 Answer
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The code you have will work as described if you substitute if-let for let. All of your conditional logic exists within the cond->.
(def initial-number 0)
(let [a true b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 6
(let [a false b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 5
(let [a true b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 1
(let [a false b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 0
answered Jan 2 at 4:06
dpassendpassen
7571510
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The code you have will work as described if you substitute if-let for let. All of your conditional logic exists within the cond->.
(def initial-number 0)
(let [a true b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 6
(let [a false b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 5
(let [a true b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 1
(let [a false b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 0
answered Jan 2 at 4:06
dpassendpassen
7571510
add a comment |
The code you have will work as described if you substitute if-let for let. All of your conditional logic exists within the cond->.
(def initial-number 0)
(let [a true b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 6
(let [a false b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 5
(let [a true b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 1
(let [a false b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 0
answered Jan 2 at 4:06
dpassendpassen
7571510
add a comment |
The code you have will work as described if you substitute if-let for let. All of your conditional logic exists within the cond->.
(def initial-number 0)
(let [a true b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 6
(let [a false b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 5
(let [a true b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 1
(let [a false b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 0
answered Jan 2 at 4:06
dpassendpassen
7571510
The code you have will work as described if you substitute if-let for let. All of your conditional logic exists within the cond->.
(def initial-number 0)
(let [a true b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 6
(let [a false b true] (cond-> initial-number a inc b (#(+ 5 %)))) => 5
(let [a true b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 1
(let [a false b false] (cond-> initial-number a inc b (#(+ 5 %)))) => 0
answered Jan 2 at 4:06
dpassendpassen
7571510
answered Jan 2 at 4:06
dpassendpassen
7571510
answered Jan 2 at 4:06
dpassendpassen
7571510
answered Jan 2 at 4:06
dpassendpassen
7571510
7571510
add a comment |
add a comment |
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