Rule Engine Style Guide

The following style recommendations are made to help keep code readable and familiar across the Identity Panel Suite.

• Treat all values as case-sensitive, even when they're not (e.g. function names, attribute or silo names in Graph objects)
  
  
• Use C style CamelCase naming for custom functions and environment variables
  
  
• Use spaces after commas, e.g. And(AD.displayName, Or(1, 2)) instead of And(AD.displayName,Or(1,2))
  
  
• Do not use spaces around = e.g. Dict(a=1, b=2) instead of Dict(a = 1, b = 2)
  
  
• Split long function calls with newlines.
  
  
• Left justify all parameters at the same function level.
  
  
• Use 2 spaces to indent. Don't use tabs.
  
  
• Use custom fuctions to express complex logic in fields that take a single-line entry
  
  
• If a custom function requires more than 3 parameters consider passing a structured object:
  MyFunc(hv) instead of MyFunc(emplType, emplStatus, givenName, preferredName, surname)
  
  
• When calling a custom function with multiple parameters consider using named arguments (remember a named parameter cannot span multiple lines):
  

  MyFunc(
    name=FirstNotNull(HV.preferredName, HV.givenName),
    status=HV.isActive
  )
      

  instead of

  MyFunc(
    FirstNotNull(HV.preferredName, HV.givenName),
    HV.isActive
  )
      

  
  
  
• Use multiple custom functions to avoid excessive length (e.g. split logic if function will exceed 6-10 lines), or if a branch of at least 3 lines is replicated more than once.
  
  

• And(
    Or(
      If(thing, this, that),
      "nevermind"
    ),
    "other thing"
  )

  
  
  
• Prefer boolean functions to boolean operators And() Or() intead of &&, ||
  
  
• Avoid unecessary parentheticals: And(true, false) instead of (And(true, false))
  
  
• Prefer string interpolation to concatenation:
  $"{HV.upnPrefix}@{special.Environment.UPNSuffix}" instead of
  HV.upnPrefix + "@" + special.Environment.UPNSuffix, remembering that nested interpolation is not supported.
  
  
• Prefer // line comments to /* block comments */. The comment should start the line.
  
  
• When transforming lists, use list reducers in the inner loop to reduce processing: 

  Map(
    Filter(list, expression),
    transformation
  )

  instead of

  Filter(
    Map(list, transformation),
    expression
  )