57 lines
1.3 KiB
Markdown
57 lines
1.3 KiB
Markdown
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# Ifs and elses
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## Syntax
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Each if statement consists of the `if` keyword, followed by an expression, encapsulated in parenthesis, followed by a statement. Optionally, the statement may be followed by an `else` keyword, which is followed by a statement on its own.
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```c#
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if (expression) statement
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// or
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if (expression) statement1 else statement2
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```
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No semicolons are required after the body of an if statement, unless the body statement itself requires one.
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## Terminology
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The given expression is called a `condition`, the statement following the condition is the `if body` and the statement following the else keyword is called the `else body`
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## Behavior
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The given expression (condition) may be of any type, and if its non-zero, then the if body will be executed. Else, if one, the else body will be executed instead.
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## Equivalent PPCIL assembly
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For any given if-else statement:
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```c
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if (condition) if_body
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else else_body
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```
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Its equivalent assembly is:
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```
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;condition
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jz else
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; if_body
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jmp end_else
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else:
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;else_body
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end_else:
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```
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If the if doesn't have a corresponding else statement, the resulting assembly is as follows:
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```
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;condition
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jz else
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; if_body
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else:
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```
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## Possible compiler optimizations
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An if body may be omitted if the condition is determined to be `false`. If the condition is determined to be `true`, then the else body is omitted.
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