Logic

Verse uses logic as the type for Boolean values, which means logic only has two possible values: true and false.

Both true and false are logic literals when you use them in Verse code.

The following is an example of how to create a logic variable named TargetLocked, initialized with the logic literal false:

var TargetLocked : logic = false
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Logic Operations

The logic type supports query operations and comparison operations.

Query

Query expressions use the operator ? (query) and check if a logic value is true. Otherwise, the expression fails if the logic value is false.

# Determine whether to show the target-locked icon if a target is locked
if (TargetLocked?):
    ShowTargetLockedIcon()
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For more on query operations, see Operators.

Comparison

For comparison operations, you can use the failable operator = to test if two logic values are equal, and the failable operator <> to test for inequality.

For example, the sample code below will make an "unavailable action" icon appear if the player has equipped a weapon but doesn't have a target, or has a target but no weapon. This can be expressed by comparing logic values that represent the two factors.

• If both are false, you won't see the icon because the player isn't trying to attack.
• If both are true, you won't see the icon because the player is able to attack.

# Initialize logic variables for demonstration purposes.
var TargetLocked : logic = false
var WeaponEquipped : logic = true
	
# Determine whether or not the "unavailable action" icon is appropriate.
if (WeaponEquipped <> TargetLocked):
    # The icon should show up, because the player appears to be trying to
    # attack, but is missing either a weapon or a target.
    ShowUnavailableIcon()
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For more on comparison operations, see Operators.

Convert Failable Expression to Logic

You can cast a failable expression to a logic type using logic{failable-expression}, where failable-expression is an expression that can fail.

In the following example, the failable expression GetRandomInt(0, MineFrequency) <> 0 is converted to the logic value false if the random integer is 0 and true otherwise.

IsMined := logic{GetRandomInt(0, MineFrequency) <> 0}
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Standard Library

The standard library provides functions to help with creating and using logic values. Refer to the Verse API Reference for more details on these functions.