Learning how to use C++ template functions in embedded projects with an Arduino.
LuckyResistor has just published C++ Templates For Embedded Code, the first in a series on the subject of C++ templates.
This is great! Although I've dabbled in C++ for years, I've never fully taken templates on board. Proving that they can be beneficial for embedded development is a bonus.
I've taken the circularShift example from the article, and extended the code a little to toggle the LED on pin 13 everytime circularShift wraps a 1 around.
One important point to note if you are copying code from the article:
The declaration and implementation of a function template have to be in a header file
With Arduino IDE 1.8.2, I get a compiler error like this if I try and put templates in the main sketch file:
UsingTemplates:12: error: variable or field 'circularShift' declared void void circularShift(Value &value) { ^ UsingTemplates:12: error: 'Value' was not declared in this scope UsingTemplates:12: error: 'value' was not declared in this scope void circularShift(Value &value) { ^ exit status 1 variable or field 'circularShift' declared void Putting the template in a header file fixes this. Also, Arduino IDE 1.8.9 does not have this issue - it can compile templates in the sketch file.
From the console, the first iterations checkout - correct right shift on both values (should improve this to include leading 0s in the output)
10101011110011010000000100100011 100010101000101 11010101111001101000000010010001 1010001010100010 11101010111100110100000001001000 101000101010001 1110101011110011010000000100100 1010100010101000 
