`<if>`

The <if> element is a conditional statement that allows you to execute a block of code based on whether a condition is true or false.

Children

This is a statement. The only elements that can be direct children of <if> are the <condition>, <then>, <elif>, and <else> elements, which aren't valid elements anywhere else.

`<condition>`

The <condition> element is used to define the condition that will be evaluated to determine whether the <then> block should be executed.

There must be exactly 1 <condition> element as a child of <if>/<elif>.

It must have a single child, which is evaluated and converted to a boolean. If the result is true, the <then> block will be executed.

`<then>`

The <then> element is used to define a block of code that will be executed if the <condition> evaluates to true. It is a block.

There must be exactly 1 <then> element as a child of <if>/<elif>.

The <then> element can access the result of the <condition> evaluation using the <special> element with the name attribute set to condition. This will return the result as the type of the value returned by the child of <condition> (but before being converted to a boolean).

`<elif>`

The <elif> element is used to define an additional condition that will be evaluated if the <condition> evaluates to false and all previous <elif> conditions also evaluated to false. It is a statement.

There can be any number of <elif> elements as children of <if>.

Each <elif> must have exactly 1 <condition> and 1 <then> element as children.

`<else>`

The <else> element is used to define a block of code that will be executed if the <condition> evaluates to false and all <elif> conditions also evaluated to false. It is a block.

There can be at most 1 <else> element as a child of <if>. If present, it must be the last child of <if>.

Example

<program>
    <set var="secret"><int>42</int></set>
    <set var="guess"><int><readline /></int></set>
    <if>
        <condition>
            <eq>
                <get var="guess" />
                <get var="secret" />
            </eq>
        </condition>
        <then>
            <print>Congratulations! You guessed the secret number!</print>
        </then>
        <elif>
            <condition>
                <lt>
                    <get var="guess" />
                    <get var="secret" />
                </lt>
            </condition>
            <then>
                <print>Your guess is too low. Try again!</print>
            </then>
        </elif>
        <else>
            <print>Your guess is too high. Try again!</print>
        </else>
    </if>
</program>

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