After including Homie.h min() function has to be called as std::min()

[furyfire]

After including Homie.h any code that uses the min() function will fail to compile unless you give it a namespace. This is unlike other Arduino libs and causes confusion.

include

include

void setup() { std::min(2,3); }

void loop() { }

[marvinroger]

It's not Homie' fault.

The min() you're using when you call the min() function is not the std one, but the one defined by a #define there. The problem is ESP8266WiFi.h undefines both min and max. You can try:

#include <ESP8266WiFi.h>

void setup() {
  min(2,3);
}

void loop() {
  delay(100);
}

It won't work either. The issue is tracked at esp8266/Arduino#398

As a workaround, you can use _min and _max.