lion/packages/form-system/docs/25-system-model-value.md

ModelValue

export default {
  title: 'Forms/System/ModelValue',
};

The modelValue or model can be considered as the ‘aorta’ of our form system. It is the single source of truth; not only for the current state of the form, also for all derived states: interaction, validation, visibility and other states are computed from a modelValue change.

Single source of truth

ModelValues are designed to provide the Application Developer a single way of programmatical interaction with the form for an Application Developer.

One single concept for Application Developers

Application Developers need to only care about interacting with the modelValue on a form control level, via:

• .modelValue
• @model-value-changed

Internal/private concepts like viewValue, formattedValue, serializedValue are therefore not recommended as a means of interaction.

For more information about parsing and the Unparseable type, see Formatting and Parsing