Tutorial

Piglet is an extremely simple language to describe flow.

1. Don’t Support

No DataType and Variable
No Operator
And of cource No Function

2. What Piglet Support

2.1 Grammar

2.1.1 Piglet Keywords

Keyword	Description
break	Terminates a switch or a loop
continue	Jumps out of a loop and starts at the top
if … elif … else	Marks a block of statements to be executed, depending on a condition
switch … case	Marks a block of statements to be executed, depending on different cases
do … while	Executes a block of statements, and repeats the block, while a condition is true
while …	While a condition is true, executes a block of statements, and repeats the block

2.1.2 Semicolons

Semicolons separate Piglet statements.

Add a semicolon at the end of each executable statement:

初始化;

2.1.3 White Space

Piglet ignores multiple spaces.

初始化   ;

2.1.4 Case Sensitive

do and DO are different.

2.2 Comments

Comments can be used to explain code, and to make it more readable.

Example:

init; # this is a comment

2.3 Conditions

Conditional statements are used to perform different actions based on different conditions.

Piglet has the following conditional statements:

Use if to specify a block of code to be executed, if a specified condition is true
Use else to specify a block of code to be executed, if the same condition is false
Use elif to specify a new condition to test, if the first condition is false
Use switch to specify many alternative blocks of code to be executed

2.4 Switch

The switch statement is used to perform different actions based on different conditions.

Use the switch statement to select one of many code blocks to be executed.

I believe you are familiar with the usage. Here is an example:

switch(size) {
  case M:
    code block;
    break;
  case L:
    code block;
    break;
  default:
    code block;
}

2.5 Loop While

Loops can execute a block of code as long as a specified condition is true.

I believe you are familiar with the usage.

2.5.1 The While Loop

while (a > 0) {
  code block to be executed;
}

2.5.2 The Do/While Loop

do {
  code block to be executed;
}
while (a > 0);

2.5.3 No Loop For

Not support for loop yet.

2.6 Break And Contnue

The break statement “jumps out” of a loop.

The continue statement “jumps over” one iteration in the loop.

Piglet Part2 - Tutorial

A language named Piglet to describe the flow chart