For example I have a Game class and it keeps an int that tracks the players lives. I have a

if ( mLives < 1 )

check and inside the if scope it does some work.

However this condition keeps firing and the work is done over and over, so for example i want to set a timer to exit the game in 5 seconds. It will keep setting it to 5 seconds every frame and the game will never end.

This is just one example, and problem repeats itself over and over in my game, I want to check for some condition and then do something once and only once, and then not check or do the code in the if statement again. Some possible solutions that come to mind are having a bool for each condition and set the bool when the condition fires, however in practice this gets very messy handling lots of bools that have to be stored in a class field, or even statically within the method itself, that would get nasty fast.

What is the proper solution to this? ( Not for my example, for the problem domain  ) How would you do this in a game?

For example, I have a Game class and it keeps an int that tracks the player's lives. I have a conditional

if ( mLives < 1 ) { // Do some work. } 

However this condition keeps firing and the work is done repeatedly. For example, I want to set a timer to exit the game in 5 seconds. Currently, it will keep setting it to 5 seconds every frame and the game never ends.

This is just one example, and I have the same problem in several areas of my game. I want to check for some condition and then do something once and only once, and then not check or do the code in the if-statement again. Some possible solutions that come to mind are having a bool for each condition and set the bool when the condition fires. However in practice this gets very messy handling lots of bools, since they have to be stored as class fields, or statically within the method itself.

What is the proper solution to this  (not for my example, but for the problem domain)? How would you do this in a game?