fragments

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sed -n '<from>,<to>p' SKILL.md one section rather than reading the file; ./mxcli syntax <topic> answers how do I write this for a fraction of either.

lines	section
24-32	When to Use This Skill
33-40	What Are Fragments?
41-189	Syntax Reference
190-259	Common Patterns
260-306	Common Mistakes
307-316	Validation Checklist
317-322	Related Documentation

Mendix Fragments Skill

When to Use This Skill

Use this skill when:

• Defining reusable widget groups with create fragment
• Inserting fragments into pages or snippets with use fragment
• Listing or inspecting fragments with list fragments / describe fragment
• Building multiple pages that share common widget patterns (footers, form fields, buttons)
• Avoiding copy-paste of repeated widget structures across pages

What Are Fragments?

Fragments are script-scoped, transient widget groups:

• Defined once, reused in multiple pages/snippets within the same script
• Not persisted in the MPR file — they exist only during script execution
• Widgets are deep-cloned on expansion (each USE gets independent copies)
• Optional prefix support to avoid name conflicts when using the same fragment multiple times

Syntax Reference

CREATE FRAGMENT

mdl 1;
create fragment SaveCancelFooter as {
  footer footer1 {
    actionbutton btnSave (caption: 'Save', action: save changes, buttonstyle: primary)
    actionbutton btnCancel (caption: 'Cancel', action: cancel changes)
  }
};

Multiple top-level widgets:

mdl 1;
create fragment CustomerFields as {
  textbox txtName (label: 'Name', attribute: Name)
  textbox txtEmail (label: 'Email', attribute: Email)
  textbox txtPhone (label: 'Phone', attribute: Phone)
};

USE FRAGMENT

Inside a page or snippet body:

mdl 1;
create page Module.CustomerEdit
(
  params: ( $Customer: Module.Customer ),
  title: 'Edit Customer',
  layout: Atlas_Core.PopupLayout
)
{
  dataview dvCustomer (datasource: $Customer) {
    use fragment CustomerFields
    use fragment SaveCancelFooter
  }
};