A variable is a named representation of some section of memory. Variables are used to store values, one of the most fundamental part of any program. Some examples of declaring variables are:
var my_variable = 123 var my_variable: Number = 123 let my_variable = 123 let my_variable: Number = 123 const my_constant = 123 const my_constant: Number = 123
let is simply an alias for
var, they are exactly the same.
Many, now considered, "low-level" programming languages such as C are "strongly" typed. This means, you cannot change the type of a variable once it has been declared. This type is passed with the variable's decleration. For example the following is invalid:
int foo = 123; // Declares `foo` as an integer; foo = "bar"; // Error: cannot make an int a string
Note: This works as well (since version v1.0.0-beta.51)
var foo := 123; // Declares `foo` as an integer foo = "bar"; // Error: cannot make an int a string
var foo = 123; foo = "bar"; // just fine
Cheddar uses both. Different programmers have different preferences on which typing is the best. Strong typing can be used as beneficial to avoid hard to debug bugs when typed automatically change. Weak typing can be helpful when quickly scripting. Cheddar suits both:
// == Weak Typing == var weak_var = 123 weak_var = "bar" // no error // == Strong Typing == var strong_var : Number = 123 strong_bar = "bar" // error
Note: If you're using a Cheddar version < 0.3 (
cheddar -V) implicit variables use the legacy
var a := b syntax.
Often times you want a variable that doesn't change, to be a "constant". Cheddar supports this, simply instead of the
var keyword, use
const my_constant = 123 my_constant = "foo"; // Error
Constants can also be strongly & weakly typed, except that the only time the type checking will ever happen is at the deceleration.