In the early days of Basic, the Let statement was needed to give a variable a value. Later, the Let statement could be omitted simply by assigning the value to the Variable:
Let a = "Hello World"
a = "Now without Let"
In VBscript, object variables were introduced and these could have a default property. To know if the programmer was refering to the default property of the object instead of the object itself (also because variables in VBscript were not strong typed), the Set statement was introduced. Let (or a plain assignment) used the default property, Set was putting the reference to the object into the variable:
'Assume an object MyField that has a default property 'Value'
Dim a, b
Let a = MyField 'Old VBscript: The Value of MyField is put into a
Set b = MyField 'Old VBscript: The reference to MyField is put into b
In Polar Script the use of the default property is not the standard anymore. It caused implicit/unclear programming and is often not intuitive. In combination with strong typing, there is no need to use the Set statement anymore:
'Assume an object MyField that has a default property 'Value'
Dim a As String
Dim b As Field
a = MyField 'Generates an error: you cannot put an object of type 'Field' into string variable a
a = MyField.Value 'This is what the programmer mean to do. OK.
b = MyField 'The reference to MyField is put into b