Elixir Pattern Matching

Elixir pattern matching just a little bit unaccustomed, in Elixir which = operators are called match operators

IEX > x = 1
1
IEX (+) > x
1
IEX (+) > 1 = x
1
IEX (+) > 2 = x
* * (Matcherror) No match of right hand side value:1

1=x legally equals 1.

An error occurs when the 2=x sides are unequal MatchError

Match list

IEX (2) > A = [1]
[1]
IEX (3) > [h|t] = a
[1]
IEX (4) > H
1
IEX (5) > t
[]

with [h|t] = A---"[h|t]=[1]--" H matches to 1 T is empty

if [h|t] = []

* * (Matcherror) No match of right hand side value: []

Matching tuples

IEX (+) > {A, B, c} = {: Hello, ' word ', 33}
{: Hello, "word", 33}
IEX (> a)
: Hello
IEX (Panax Notoginseng) > B
"Word"
IEX (> C)
33

Both sides do not match

IEX ($) > {A, B, c} = {: Hello, ' word '}
* * (Matcherror) No match of right hand side value: {: Hello, "word"}

The first one on the right is not: OK also does not match

IEX (+) > {: OK, result} = {: OK, 13}
{: OK, 13}
IEX ($) > result
13
IEX > {: OK, result} = {: Error,: oops}
* * (Matcherror) No match of right hand side value: {: Error,: oops}

Elixir Pattern Matching