Superoperators

Superoperators allow AbstractLogic to evaluate multiple expressions simultaneously. Common type of expressions to be evaluated in this way are if ... then (==>), if (<==), and if only if (iff/<=>/===) statements. Generally superoperators can be identified by noting that they have three symbols together making up the operator or are strings in lowercase.

When AbstractLogic encounters a superoperator it evaluates any expressions on either side of the superoperator. These expressions are returned as true or false. Then it follows the rules of the superoperator to evaluate the joint expression.

Constraint: a > b ==> c == a = x ==> y with x = a > b and y = c == a

A simple example.

A right arrow if constraint (==>) only holds if the left side is true. x (a > b) is true so y (c == a) must also be true. In row 1, x is true but y is not so the total statement returns false. In row 2, x is true and y is true so the total statement returns true. In row 3 the conditional statement x is false so the constraint does not bind and the total expression returns true.

Operators

Notationally x, y, and z will refer to operations composed of at least one operator.

x &&& y

Both x and y must be true. Command end operator ; is often preferred to joint evaluators since it is more efficient. In x ; y efficiency is gained by evaluating x first, reducing the feasible set, then evaluating y.

Note x and y is equivalent

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b &&& b > c
a > b &&& b > c                  feasible outcomes 1 ✓✓          :3 2 1

x ||| y

Either x or y could be true. Only if both are false or then total expression will return false.

Note x or y is equivalent

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b ||| b > c
a > b ||| b > c                  feasible outcomes 17 ✓          :2 2 1

x !== y

Either x or y must be true but not both. If both are false or both are true then it will return false.

Note x xor y and x ^^^ y is equivalent (x and y can only be true or false)

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b ^^^ b > c
a > b ^^^ b > c                  feasible outcomes 16 ✓          :3 3 2

x === y

If x = true then y = true or if x = false then y = false.

Note x iff y and x <=> y are equivalent

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b === b > c
a > b === b > c                  feasible outcomes 11 ✓          :1 2 2

x ==> y

If x = true then y must be true.

Note if x then y and x then y are equivalent

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b ==> b > c
a > b ==> b > c                  feasible outcomes 19 ✓          :3 3 3

x !=> y

If x = false then y must be true.

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b !=> b > c
a > b !=> b > c                  Feasible Outcomes: 17   Perceived Outcomes: 27 ✓        :3 2 1

x <== y

If y = true then x must be true.

Note x if y is equivalent

Example

abstractlogic> a,b,c ∈ 1:3
a,b,c ∈ 1:3              feasible outcomes 27 ✓          :1 1 3
abstractlogic> a > b <== b > c
a > b <== b > c                  feasible outcomes 19 ✓          :3 1 1

Chaining Operators

Superoperators can be chained and when evaluated are evaluated from left to right.

Note true and false are replaced dynamically in AbstractLogic with 1==1 and 1==0.

Activate the abstractlogic repl by typing = in console.

abstractlogic> a ∈ 1
a ∈ 1                    feasible outcomes 1 ✓✓          :1

abstractlogic> true
true                     feasible outcomes 1 ✓✓          :1

abstractlogic> false
false                    feasible outcomes 0 X            [empty set]

abstractlogic> back
Last command: "true" - Feasible Outcomes: 1     :1

abstractlogic> true or false
true or false            feasible outcomes 1 ✓✓          :1

abstractlogic> true or false and true
true or false and true   feasible outcomes 1 ✓✓          :1

abstractlogic> true xor false
true xor false           feasible outcomes 1 ✓✓          :1

abstractlogic> true xor false xor true
true xor false xor true          feasible outcomes 0 X            [empty set]

The last expression returns an empty set (false) because it evaluates from left to right (true xor false) xor true which becomes (true) xor true which is then evaluated at false.

Note Wildcards are spawned on the level right above superoperators. See Wildcards for more information.