Lua Programming/How to Lua/operator

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The lua programming language provides a series of operators that allow values and variables to be compared, evaluated or manipulated. These operators can combined together with values and variables to make expressions. The operators may take unary, dyadic or ternary form, depending on the number of operands that they utilize.

Assignment Operator[edit]

As within most other programming languages, the equals sign acts as a dyadic operator, assigning the value of the expression of the right hand operand to the variable named by the left operand.

Arithmetic operators[edit]

  • arithmetic operators

The lua programming language provides a standard set of arithmetic operators for manipulating integer and floating point numbers.

String operators[edit]

  • string operators

Logical operators[edit]

  • logical operators

The logical operators are used to perform boolean operations, returning either true or false.

Bitwise operators[edit]

  • bitwise operators

The bitwise operators are used to perform manipulation of binary numbers.

Nudge operators[edit]

The lua programming language does not support the plusplus or dashdash increment or decrement operators. The dashdash symbol is interpreted as a comment marker in lua.

Comparative operators[edit]

  • comparative operators

Regular expression operators[edit]

  • regular expression operators

Numeric operators[edit]

  • numeric operator

Comma operator[edit]

  • comma

Relationship operators[edit]

  • relationship operators

Reference operators[edit]

  • reference operator

Dereference operators[edit]

  • dereference operator

Arrow operator[edit]

  • arrow operator

Length operator[edit]

In lua, the hash symbol acts as a length operator.

Combination assignment operators[edit]

The lua programming language does not support the combination assignment operators.

Ternary operators[edit]

  • ternary operator

Scope resolution[edit]

The percent symbol can be used as a prefix operator enabling a variable within the scope of a function to be referenced from its containing outer function.