An `import` statement followed by a curly brace enclosed list of names
will import the corresponding exports from the module.

-- Testcase --
import { a, b, c } from "./files/test1.uc";

print([ a, b, c ], "\n");
-- End --

-- File test1.uc --
export const a = 1, b = 2, c = 3;
-- End --

-- Args --
-R
-- End --

-- Expect stdout --
[ 1, 2, 3 ]
-- End --


Attemping to import a not exported name will raise an error.

-- Testcase --
import y from "./files/test2.uc";

print(y, "\n");
-- End --

-- File test2.uc --
export const x = "This is a test";
-- End --

-- Args --
-R
-- End --

-- Expect stderr --
Syntax error: Module ./files/test2.uc has no default export
In [stdin], line 1, byte 15:

 `import y from "./files/test2.uc";`
  Near here ----^


-- End --


Imports may be renamed to assign an alternative local name to the
exported module symbols. Renaming is also required for string export
names which are no valid variable identifiers.

-- Testcase --
import { a as var1, bool as var2, "my function" as var3 } from "./files/test3.uc";

print([ var1, var2, var3 ], "\n");
-- End --

-- File test3.uc --
const a = "A string";

let b = 123;

function c() {
	return "A function"
}

export {
	a,
	b as bool,
	c as "my function"
};
-- End --

-- Args --
-R
-- End --

-- Expect stdout --
[ "A string", 123, "function c() { ... }" ]
-- End --


A list expression may follow a default import expression in an `import`
statment.

-- Testcase --
import defVal, { a as x, b as y, c as z } from "./files/test4.uc";

print([defVal, x, y, z], "\n");
-- End --

-- File test4.uc --
export const a = 1, b = 2, c = 3;
export default a + b + c;
-- End --

-- Args --
-R
-- End --

-- Expect stdout --
[ 6, 1, 2, 3 ]
-- End --