Create your functions

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Create a function

We have already used several standard functions (setWeapon, moveToward, etc.). It is also possible to create your own personal functions, with the following syntax:

Keyword function
Name of the function: sum
List of the function's parameters, in parentheses ( x, y )
Instruction block, in braces { x + y }

The return keyword, optional, is used to make the function return a value. In the previous example, the function takes the parameters x and y and returns their sum: x + y.

Creating a `canFinish(enemy)` function

Our previous code for the "finish" condition of the enemy is quite large and not very reusable, so we will put it in a function.

We will create a personal function canFinish(enemy), which takes an enemy and returns a boolean indicating whether we can finish it or not.

We copy the finisher code into a function written this way:

note: remember to specify which weapon you are talking about so that the calculation works. Also, the function returns true if you have enough turn points to fire enough shots at the enemy for it to die, and false if on the contrary it will survive (so you can perhaps do something else).

Now, we can use our canFinish function in our main code to write it much more simply:

Did you know? Moving the same code multiple times into a function is called Factorization.

Creating a `getClosestCellToUseWeapon(enemy)` function

You may have noticed that to use the Machine Gun weapon or later the Laser, you must be in line with the enemy.

You will therefore have to go to a cell from which you can use your weapon, instead of simply moving toward the enemy as with the Pistol.

For this, there is the standard function getCellsToUseWeapon, which returns all possible cells to use a weapon on a target. You will therefore have to choose one: the closest!

So we will create a getClosestCellToUseWeapon function and use a for in loop to calculate the cell whose distance to us is the shortest:

We use it to replace the moveToward movement:

If you feel comfortable, you can code the following functions:

estimateDamage(weapon, enemy): calculates the damage that the weapon will inflict on enemy.
getBestWeapon(enemy): searches among your weapons for the one that does the most damage on enemy.

You can also:

Check that an ally is not in the usage zone of a weapon: standard function getWeaponTargets.
Check that you are not attacking a bulb instead of an enemy leek: standard function getType.

To better see the terrain and the cells, do not hesitate to use the tactical mode by pressing T in combat.

In the following chapters we will tackle more difficult aspects so take the time to play with your functions and the concepts we have seen previously, which are already enough to climb in the ranking!

❓ Quiz

Which function that returns the square of a number is correct?

function square(x) { return x * x } function square(x) { x * x } function square() { return x * x } fonction square(x) { return x * x }

Which function calculates the maximum of a list?

function maximum(list) { var max = -99999 for (var e in list) { if (e > max) { max = e } } return max } function maximum(list) { var max = 99999 for (var e in list) { if (e < max) { max = e } } return max } function maximum(list) { var max = 99999 for (var e in list) { if (e > max) { max = e } } return max } function maximum(list) { var max = -99999 for (var e in list) { if (e < max) { max = e } } return max }

Create your functions