# BCPNFR17 - Code Styling - Type casting

Module Specification for the Azure Verified Modules (AVM) program

ID: BCPNFR17 - Category: Composition - Code Styling - Type casting To improve the usability of primitive module properties declared as strings, you SHOULD declare them using a type which better represents them, and apply any required casting in the module on behalf of the user.
For reference, please refer to the following examples:
Boolean as String Boolean as String Before After @allowed([ &#39;false&#39; &#39;true&#39; ]) param myParameterValue string = &#39;false&#39; resource myResource &#39;(...)&#39; = { (...) properties: { myParameter: myParameterValue } } param myParameterValue string = false resource myResource &#39;(...)&#39; = { (...) properties: { myParameter: string(myParameterValue) } } Integer Array as String Array Integer Array as String Array Before After @allowed([ &#39;1&#39; &#39;2&#39; &#39;3&#39; ]) param zones array resource myResource &#39;(...)&#39; = { (...) properties: { zones: zones } } @allowed([ 1 2 3 ]) param zones int[] resource myResource &#39;(...)&#39; = { (...) properties: { zones: map(zones, zone =&gt; string(zone)) } } 

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Source: https://raw.githubusercontent.com/Azure/Azure-Verified-Modules/refs/heads/main/docs/content/specs-defs/includes/bicep/shared/non-functional/BCPNFR17.md
Last Modified: 0001-01-01