Merge pull request #6811 from roc-lang/tutorial-fix-capitalized

isCapitalized > startsWith

www/content/tutorial.md

@@ -698,7 +698,7 @@ We can use tags with payloads to make a list that contains a mixture of differen
 List.map [StrElem "A", StrElem "b", NumElem 1, StrElem "c", NumElem -3] \elem ->
     when elem is
         NumElem num -> Num.isNegative num
-        StrElem str -> Str.isCapitalized str
+        StrElem str -> Str.startsWith str "A"
 # returns [Bool.true, Bool.false, Bool.false, Bool.false, Bool.true]
 ```
 
@@ -708,7 +708,7 @@ Compare this with the example from earlier, which caused a compile-time error:
 List.map ["A", "B", "C", 1, 2, 3] Num.isNegative
 ```
 
-The version that uses tags works because we aren't trying to call `Num.isNegative` on each element. Instead, we're using a `when` to tell when we've got a string or a number, and then calling either `Num.isNegative` or `Str.isCapitalized` depending on which type we have.
+The version that uses tags works because we aren't trying to call `Num.isNegative` on each element. Instead, we're using a `when` to tell when we've got a string or a number, and then calling either `Num.isNegative` or `Str.startsWith` depending on which type we have.
 
 We could take this as far as we like, adding more different tags (e.g. `BoolElem Bool.true`) and then adding more branches to the `when` to handle them appropriately.