Code Rules

This page defines constraints and API guidance for generating C# used by code-based transformations.

Use these with code-transformation generation tasks.

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Rule source ids

Value	Purpose
Code	Base C# generation rules and runtime API guidance.
MirthCode	Mirth script conversion guidance into C#.
AllCode	Concatenates base + Mirth code guidance.

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Rule selection behavior

• always includes Code
• adds MirthCode when filter contains mirth

Non-obvious outcome

• selector is binary (base vs base+Mirth), not task-granular.
• if you need both transformer-shape guidance and code-style guidance, combine this with transformer rules in the same generation request.

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Code output contract

Generated output should follow these constraints:

• return plain C# only
• no markdown fences
• target .NET Framework 4.8 compatibility
• use runtime APIs exposed to workflow code context
• avoid inventing unsupported properties or helper classes

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Composition pattern

When generating a code transformer payload:

1. build/validate non-code transformer plan first
2. identify the exact step(s) requiring code
3. call CreateCodeTransformers with:
4. activity message type context
5. required input/output variable paths
6. strict expected result shape (Code body only or code action payload shape)

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Worked scenarios

Example 1: expression too complex for map/update action

Intent:

Normalize a patient surname with McNameCase, preserve original when empty.

Expected result:

• generated C# implementing normalization logic
• code can be embedded in a code transformer action

Example 2: Mirth JavaScript conversion

Filter token includes mirth.

Expected result:

• JavaScript channel logic translated to C#
• variable access and message path access translated to HL7 Soup runtime patterns

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Failure modes to avoid

• returning mixed prose + code
• using language features or APIs not available to target runtime
• generating code that assumes unavailable sender/receiver instances without context binding