Grammar and Subgrammar Structure

Grammar & Subgrammar Structure

Crodox uses a file-based grammar structure where files can include subgrammars to compose complex language definitions.

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File Composition (Top-to-Bottom)

The grammar follows a top-to-bottom hierarchy. Objects defined higher up are inherited by all subgrammars below. Objects inside a subgrammar are not counted additionally at the parent level.

graph TD
    MAIN["<b>File.xy</b><br/>&lt;~ &quot;FROM1&quot;.xy ~&gt;"] --> OA["objectA"]
    MAIN --> OB["objectB"]
    MAIN --> SERVICE["<b>File.service.xy</b><br/>&lt;~ &quot;FROM2&quot;.service.xy ~&gt;"]
    MAIN --> OE["objectE"]
    MAIN --> MODULE["<b>File.module.xy</b><br/>&lt;~ &quot;FROM3&quot;.module.xy ~&gt;"]

    SERVICE -.->|"inherits"| OA
    SERVICE -.->|"inherits"| OB
    SERVICE --> OC["objectC"]
    SERVICE --> OD["objectD"]
    SERVICE -.->|"inherits"| OE

    MODULE -.->|"inherits"| OA
    MODULE -.->|"inherits"| OB
    MODULE -.->|"inherits"| OE
    MODULE --> OF["objectF"]
    MODULE --> OG["objectG"]

    style MAIN fill:#4a90d9,color:#fff
    style SERVICE fill:#7b68ee,color:#fff
    style MODULE fill:#7b68ee,color:#fff
    style OC fill:#7b68ee,color:#fff
    style OD fill:#7b68ee,color:#fff
    style OF fill:#7b68ee,color:#fff
    style OG fill:#7b68ee,color:#fff

Loading

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How It Works

Files can nest subgrammars using the file syntax. Each subgrammar inherits objects from its parent scope and adds its own definitions.

Example

<~"FROM1".xy~>
    <*objectA*> objectA <*>
    <*objectB*> objectB <*>

    <~"FROM2".service.xy~>
         <*objectC*> objectC <*>
         <*objectD*> objectD <*>
    <~>

    <*objectE*> objectE <*>

    <~"FROM3".module.xy~>
         <*objectF*> objectF <*>
         <*objectG*> objectG <*>
    <~>
<~>

Resulting Visibility

File	Visible Objects
File.xy	objectA, objectB, objectE
File.service.xy	objectA, objectB, objectC, objectD, objectE
File.module.xy	objectA, objectB, objectE, objectF, objectG

Rule: Objects defined at the top level are visible in all subgrammars. Objects defined within a subgrammar are only visible within that subgrammar's scope.

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Priority

When two object definitions match the same input, the upper definition takes priority. Objects are matched in the order they are defined - top to bottom.

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See also: Dependency Structure - How objects form dependency trees.