Home

• explain
• command-line
• schemas
  • b: ms: base
  • c: msc: concept
• contact

MS Base

• prefix: ms:
• schema: b:

Categories (Data):

• constants
• documentation
• definitions
• payloads
• units
• values

Categories (Governance):

• collections
• namespaces
• rules
• server

definitions:

• b:definitions
• b:exclude
• b:has
• b:include
• b:let
• b:set
• b:shadow
• b:use

Schema element "b:let"

Name an expression.

Definitions

<element name="let" type="b:Let" />

<complexType name="Let">
  <complexContent>
    <extension base="b:Reusable">
      <sequence />
      <attribute name="expr"   type="b:Expression" />
      <attribute name="string" type="string" />
      <attribute name="regexp" type="string" />
    </extension>
  </complexContent>
</complexType>

Description

Expressions which are defined with let can be used in other expressions. See expressions.

Many objects produce expressions. For instance, the server will offer some system values via this mechanism, like system.now. The Collection will provide expressions about, for instance, it's contained number of Units. In a Unit context, the unit.state will be set.

You MUST either use exactly one attribute from b:expr, b:string, or b:regexp. Attribute b:string can be converted into a b:expr by wrapping it in quotes.

Examples

<let name="address" string="Postbus 1428AB" />
<let name="address" expr="'Postbus 1428AB'" />
<let name="address" expr='"Postbus 1428AB"' />

<let name="pobox_nr" string="1428AB" />
<let name="address" expr="'Postbus ' ~ pobox_nr" />
<let name="address" expr='"Postbus " ~ pobox_nr' />