Question regarding daml `Ambiguous occurrence` error

Questions
1

G-d willing

I have a question about how daml interprate function names and data types.
The situation goes as follows, let’s say I have a file name Use.daml and i declare in it the following function:

firstValue : Int
firstValue = 5

later at that file I want to use this firstValue such as:

  let myValue = firstValue

Up to this point, everything is okay and works normally. However, now I decide to add another file named DataType.daml. In this file I declare the following data type:

data SomeDataType = SomeDataType with
  firstValue : Int

So, now, when I import this DataType.daml into Use.daml I am getting an error on the let command, saying Ambiguous occurrence and I don’t understand why.
I would understand it if in the DataType.daml file I will have another function with the same name.

Can someone please help me understand the reason for this?

2

Without going too much into the underlying details, the simple explanation is that data type fields are, in Daml, functions. So you really do have two functions called firstValue in scope.

The solution here is qualified imports, which I’ve explained in more details in the past.

3

Thanks @Gary_Verhaegen,
I am aware of the imports as qualified, however, how can I specify to use my local function firstValue and not the one from the import?

4

When you import a library without the qualified keyword, you get its exported names (default: all) both as qualified and unqualified. The same is true of the current module. Here’s a short example.

Lib.daml

module Lib where

one : Int
one = 1

ambiguous : Text
ambiguous = "Lib"

Main.daml

module Main where

import Daml.Script
import Lib

ambiguous : Text
ambiguous = "Main"

setup : Script ()
setup = script do
  debug $ one
  debug $ Main.ambiguous -- using the name of the current module
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