Variable Declaration

Variables in Morph are declared using the is keyword, or optionally without it using bare declaration syntax.

---

Basic Declaration with is

The is keyword binds a name to a value:

x is 10;
name is "Alice";
pi is 3.14159;
active is true;

---

The is Keyword Is Optional

In Morph, is is optional. You can declare variables without it:

// With 'is' — recommended for variables
x is 10;
name is "hello";

// Without 'is' — shorthand form
y 20;
count 0;

Convention

Context	Recommendation
Variable declaration	Use is — e.g., x is 10;
Variable reassignment	Use is — e.g., x is 20;
Method declaration	Omit is — e.g., Run method() { }
Class declaration	Omit is — e.g., Player class { }

Both forms compile identically. The convention improves readability.

---

Bare Declaration

Declaring a variable name alone (without a value) creates an uninitialized dynamic variable:

a;          // dynamic, uninitialized
b 10;       // int, value is 10
c as int;   // int, uninitialized (typed but no value)
d is 0 as dynamic;  // explicit dynamic with initial value

---

Type Annotation with as

Use as to explicitly specify the type:

x is 10 as int;
name is "hello" as string;
ratio is 0.5 as float;
flag is true as bool;

When as is omitted, the compiler infers the type from the assigned value.

---

Examples from Real Code

// From Hello.mx
x is 10;
Init is method() {
    Print(x);
};

// From IsOptionalDynamic.mx — all valid declarations
a;              // bare declaration (dynamic)
b 10;           // shorthand (int, value 10)
c as dynamic;   // typed declaration (dynamic, no value)
d is 0 as dynamic;  // full form

---

Next Steps

• Assignment — Reassigning variables and alias semantics
• Copying — Creating independent copies with another
• Move — Transferring ownership with move