58 lines
1.4 KiB
Markdown
58 lines
1.4 KiB
Markdown
# If-Else statement
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An if-else statement lets you specify which portions to code the interpreter must run based on the result of an expression.
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The syntax of an if-else statement is the following:
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```py
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if condition: {
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# Executed when the condition is true
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} else {
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# Executed when the condition is false
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}
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```
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The condition may be any type of expression, but must evaluate to a boolean type. No implicit casts are performed.
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When the `else` block is empty, in can me omitted:
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```py
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if condition: {
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# Executed when the condition is true
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}
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```
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If the blocks only contain one statement, it's possible to omit the curly brackets:
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```py
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if condition:
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doSomething();
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else
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doSomethingElse();
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```
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## If-else chains
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Since curly brackets can be dropped for blocks with only one statement, the following code:
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```py
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if cond0: {
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doSomething();
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} else {
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if cond1: {
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doSomethingElse();
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} else {
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doSomethingDumb();
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}
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}
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```
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can be simplified to
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```py
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if cond0: {
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doSomething();
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} else if cond1: {
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doSomethingElse();
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} else {
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doSomethingDumb();
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}
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```
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creating a chain of if-else statements.
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## Compound statements
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Actually the meaning of the curly brackets is to group multiple statements into one.
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The if-else statement expects only one statement for each branch, though it's possible to provide more than one statement each by wrapping them into curly brackets. |