alistairv
alistairv
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Created by alistairv on 7/14/2023 in #help
❔ Pattern matching on multiple cases with the same-typed members
Hello, I am currently stuck with code like this: 
public void Foo(Bar bar) {
  if (bar is Bar1 { Prop1: var p1 }) {
    // do stuff with p1
  } else if (bar is Bar2 { Prop2: var p2}) {
    // do the exact same stuff with p2
  } 
  // etc
}
public void Foo(Bar bar) {
  if (bar is Bar1 { Prop1: var p1 }) {
    // do stuff with p1
  } else if (bar is Bar2 { Prop2: var p2}) {
    // do the exact same stuff with p2
  } 
  // etc
}
where Bar1 : Bar, Bar2: Bar, ... and the type of Prop1, Prop2, ... is the same. Since Bar is not my type, I cannot simply modify it to suit me better. My question: Is there a way to handle this more elegantly inside the method (aside from extracting a local function)? I am thinking of some syntax like 
if (bar is Bar1 { Prop1: var p } or Bar2 { Prop2: p } or ...) { 
  // do stuff with p 
}
if (bar is Bar1 { Prop1: var p } or Bar2 { Prop2: p } or ...) { 
  // do stuff with p 
}
but unfortunately this is invalid syntax. Same holds for 
TypeOfProp p = null;
if (bar is Bar1 { Prop1: p } or Bar2 { Prop2: p } or ...) { 
  // do stuff with p 
}
TypeOfProp p = null;
if (bar is Bar1 { Prop1: p } or Bar2 { Prop2: p } or ...) { 
  // do stuff with p 
}
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