Boolean data type has two possible truth values to represent logic.
:package: Package,
:blue_book: Wiki.
Here is my implementation of digital logic gates in software. That includes
the basic gates not, and, or, xor; their complements nand, nor,
xnor; and 2 propositional logic (taught in discrete mathematics) gates
imply, eq; and their complements nimply, neq. There is also a
multiplexer, called select, and a true counter, called count. count
can help you make custom gates, such as an alternate concept of xnor
which returns true only if all inputs are the same (standard xnor returns
true if even inputs are true). All of them can handle upto 8 inputs.
parse is influenced by "boolean" package, and is quite good at translating
string to boolean. It can also handle double negatives, eg. not inactive.
You know the and of 2-inputs, but what of 1-input? What of 0? And what of
the other gates? I answer them here.
Stability: Experimental.
import Boolean exposing (..)
parse "1"
parse "truthy"
parse "not off"
-- True
parse "not true"
parse "inactive"
parse "disabled"
-- False
imply True False
-- False
eq False False
-- True
xor3 True True True
-- True
select3 1 True False True
-- False ^
count3 True True False
-- 2 ^ ^Index
| Function | Action |
|---|---|
| parse | Converts string to boolean. |
| not | Checks if value is false. |
| and | Checks if all values are true. |
| or | Checks if any value is true. |
| xor | Checks if odd no. of values are true. |
| nand | Checks if any value is false. |
| nor | Checks if all values are false. |
| xnor | Checks if even no. of values are true. |
| eq | Checks if antecedent ⇔ consequent. |
| neq | Checks if antecedent ⇎ consequent. |
| imply | Checks if antecedent ⇒ consequent. |
| nimply | Checks if antecedent ⇏ consequent. |
| select | Checks if ith value is true. |
| count | Counts no. of true values. |
