if (roll option)

[if():] Roll Option

* Introduced in version 1.3b46

Branches the flow of the roll as determined by the condition.

Usage

[if(condition): true_body]

[if(condition): true_body; false_body]

Parameters

• condition - The condition/s to check to determine which roll (true_body or false_body) is executed, if any. The condition/s can only contain one level of nested parenthesis.
• true_body - The roll that is executed if the condition evaluates to true(1). To use complex rolls in the true_body, you must use the [code():] roll option in conjunction with this roll option.
• false_body - The roll that is executed if the condition evaluates to false(0). If no false_body is given, there is no output if the condition evaluates to false(0). To use complex rolls in the false_body, you must use the [code():] roll option in conjunction with this roll option.

Operators
Operators are used to compare two variables, strings, literal numbers, expressions, or function outputs within a condition.

Conditional Operators:

• > - Greater than
• < - Less than
• >= - Greater than or equal to
• <= - Less than or equal to
• == - Equal to
• != or ne - Not equal

Logical Operators:

• && - And
• || - Or

Boolean Operators:

• true
• false
• ! - Not

It is important to note that the Equal to condition operator must be two equal signs (==). If you are checking for a text string, place quotes around the text.

-- Known Problems

• Number of () levels

The [if():] doesn't allow more than one level of (). So,

[R, if(((1))): "true";"false"]

will give an error.

• Help! There are ' ' in the output

Note that currently

[r,if(val == something),CODE:{Print something}]

will produce extraneous single quotes in the output when the condition is false. The workaround for this is to add an empty block for the false side:

[r,if(val == something),CODE:{Print something};{}]

Example

Sets the variable newVal to 12*12 if the variable val equals 12.

[h:val=12]
[h,if(val == 12): newVal=12*12]
New Value = [r: newVal]

Returns New Value = 144

Example with logical operators:

[h,if((val > 12 && val < 24) || val == 5): val=1 ; val=0]

These examples perform the same function. If val is not a number, make val equal 0.

[h, if (! isNumber(val)): val = 0)]

[h, if (isNumber(val) == 0): val = 0)]

[h, if (isNumber(val) == false): val = 0)]

The following will generate an error:

[h,if(getName(getSelected()) == "Giant Rat"): val=1]  --- ERROR, too many parenthesis on condition!
[h,if(getName() == "Giant Rat")): val=1] ---  This is OK.

See Also

if(), isNumber(), [code():], Introduction to Macro Branching