Predefined Process Shape

The Predefined Process shape (also called Subroutine) represents a process that is defined elsewhere, such as a function call, module, or subroutine.

What is a Predefined Process Shape?

The Predefined Process shape represents:

• Function or method calls
• Subroutines and procedures
• External modules
• Reusable processes
• Library functions
• Predefined operations

According to ISO 5807, this shape indicates a named process defined in detail elsewhere.

When to Use

Use the Predefined Process shape for:

• Function calls: "ValidateEmail()", "CalculateTax()"
• Modules: "AuthenticationModule", "PaymentProcessor"
• Subroutines: "SortArray()", "SendNotification()"
• API calls: "CallExternalAPI()", "FetchUserData()"
• Reusable processes: Operations defined in other flowcharts

Visual Appearance

In DiagramKit.AI, the Predefined Process shape appears as:

• Dimensions: 160×80 pixels
• Color: Light blue (#eff6ff)
• Border: Dark blue (#1e40af)
• Shape: Rectangle with double vertical lines on sides

Best Practices

✅ Good Usage

[Start]
   ↓
[Get email input]
   ↓
[ValidateEmail(email)]
   ↓
<Valid?>
  ↙    ↘
Yes    No
 ↓      ↓
[Send  [Show
 Email()] error]

• Use function-style names with parentheses
• Indicate parameters when relevant
• Show module names clearly
• Reference external processes

❌ Avoid

• ❌ Simple operations: "Add numbers" (use Process)
• ❌ One-time steps: "Print message" (use Process)
• ❌ Too vague: "Function" (which function?)
• ❌ Inline processing (should be reusable)

Common Examples

Example 1: Authentication Flow

[Enter credentials]
   ↓
[ValidateCredentials(username, password)]
   ↓
<Valid?>
  ↙    ↘
Yes    No
 ↓      ↓
[Generate [Show
 Session()] error]

Example 2: Payment Processing

[Checkout]
   ↓
[ValidateCart()]
   ↓
[CalculateTotals()]
   ↓
[ProcessPayment(amount, card)]
   ↓
<Success?>
  ↙      ↘
Yes      No
 ↓        ↓
[Send    [Refund()]
 Receipt()]

Example 3: Data Processing

[Load data]
   ↓
[CleanData()]
   ↓
[TransformData()]
   ↓
[ValidateData()]
   ↓
[SaveToDatabase()]

AI Prompt Tips

add subroutine to validate email
insert predefined process for authentication
create function call to process payment

Related Shapes

• Process - For inline operations
• Manual Operation - For manual tasks
• Preparation - For setup
• Decision - For checking results