Language - Assignment

1 - About

An assignment statement gives a value to a variable.

3 - Type and syntax

3.1 - Implicit

3.1.1 - Simple form

In its simplest form, an assignment statement has a variable on the left of the = sign and an expression on the right. This ordered form, and similar variations, is quite prevalent in modern programming languages.

variableName = value
  • Other variations exists but are less prevalent.
value -> variableName
// or
value <- variableName

Generally in a language syntax,

3.1.2 - Tuple

A tuple assignment allows several variables to be assigned at once.

Example: x becomes y and vice versa.

x, y = y, x

3.1.3 - Operator (Compound)

An assignment operator (also known as Compound operator) is a short cut language structure that combine a math operation with assignment,

Example:

x = x * scale

can be rewritten as

x *= scale

The same is true for all:

Example of compound operator:

  • +=,
  • -=,
  • *=,
  • /=

3.2 - Explicit

Assignment statements are an explicit form of assignment, but there are many places in a program where an assignment occurs implicitly:

  • a function call implicitly assigns the argument values to the corresponding parameter variables;
  • a return statement implicitly assigns the return operands to the corresponding result variables;
  • and a literal expression for a composite type such as an array

Go Example:

medals := []string{" gold", "silver", "bronze"}

implicitly assigns each element, as if it had been written like this:

medals[ 0] = "gold" 
medals[ 1] = "silver" 
medals[ 2] = "bronze"

4 - Documentation / Reference

code/grammar/assignment.txt ยท Last modified: 2017/09/17 17:39 by gerardnico