#include — Maple v0.0.12 Documentation

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# `#include`

`#include` is used to include outside libraries in your sketch. This gives the programmer access to a large group of standard C libraries (groups of pre-made functions and data types), and also libraries written especially for Maple.

## Example

This example (from the Arduino LiquidCrystal Tutorial) includes a library that is used to control LCD displays:

    // include the library code:
    #include <LiquidCrystal.h>

    // initialize the library with the numbers of the interface pins
    LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

    void setup() {
      // set up the LCD's number of columns and rows:
      lcd.begin(16, 2);
      // Print a message to the LCD.
      lcd.print("hello, world!");
    }

    void loop() {
      // set the cursor to column 0, line 1
      // (note: line 1 is the second row, since counting begins with 0):
      lcd.setCursor(0, 1);
      // print the number of seconds since reset:
      lcd.print(millis()/1000);
    }

Note that a `#include` line, like #define, has no semicolon. The compiler will print strange error messages if you add one.

## C Standard Library

The standard C library that comes with Maple is called newlib. Its main sources of documentation are its main reference page and its math functions reference page. Here’s an example that imports the math.h library in order to take the cube root of a number:

    #include <math.h>

    void setup() {
        // no setup necessary
    }

    void loop() {
        // "cbrt" stands for "cube root"
        double cubeRootOf3 = cbrt(3.0);
        // prints a number that is approximately the cube root of 3:
        SerialUSB.println(cubeRootOf3);
    }

License and Attribution

Portions of this page were adapted from the Arduino Reference Documentation, which is released under a Creative Commons Attribution-ShareAlike 3.0 License.

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