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diff --git a/source/arduino/if.rst b/source/arduino/if.rst deleted file mode 100644 index 89af166..0000000 --- a/source/arduino/if.rst +++ /dev/null @@ -1,81 +0,0 @@ -.. highlight:: cpp - -.. _arduino-if: - -if Statements -============= - -An ``if`` statement is used to execute code when certain conditions -are met. The general syntax for an ``if`` statement is:: - - if (condition) { - body - } - -An ``if`` statement first tests whether its *condition* is true (such -as an input being above a certain number). If the condition is true, -the ``if`` statement executes its *body*, which is made up of lines of -code inside :ref:`curly braces <arduino-braces>`. If the condition is -false, the body is not executed. Here's a more concrete example:: - - if (someVariable > 50) { - // do something here - } - -The program tests to see if ``someVariable`` is greater than 50. If it -is, the program executes every line in the curly braces (which in the -above example does nothing, since the body is just the :ref:`comment -<arduino-comments>` line "``// do something here``"). - -Put another way, if the statement in parentheses is true, the -statements inside the braces are run. If not, the program skips over -the code. - -An ``if`` statement's condition (which is inside the parentheses after -``if``) often uses one or more :ref:`boolean <arduino-boolean>` or -:ref:`comparison <arduino-comparison>` operators. - -Writing the if Body -------------------- - -The brackets may be omitted after an ``if`` statement's -conditional. If this is done, the next line (which ends in a -semicolon) becomes the only line in the body. The following three -``if`` statements all do the same thing:: - - if (x > 120) digitalWrite(ledPin, HIGH); - - if (x > 120) - digitalWrite(ledPin, HIGH); - - if (x > 120) { - digitalWrite(ledPin, HIGH); - } - -However, the following two examples are different:: - - // example 1: two lines of code in the if body - if (x > 120) { - digitalWrite(ledPin1, HIGH); - digitalWrite(ledPin2, HIGH); - } - - // example 2: one line of code in the if body, and - // another line of code after the if statement - if (x > 120) - digitalWrite(ledPin1, HIGH); // this is in the if body - digitalWrite(ledPin2, HIGH); // this is NOT in the if body - -In the first example, since the body is enclosed in curly braces, both -lines are included. In the second example, since the curly braces are -missing, only the first line is in the ``if`` body. - -See Also --------- - -- :ref:`boolean operators <arduino-boolean>` -- :ref:`comparison operators <arduino-comparison>` -- :ref:`else <arduino-else>` - - -.. include:: cc-attribution.txt
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