dictionary.get error?

[milen-prg]

`

import dictionary

let d = dictionary<string, int>{size: 5}

d.add("p1", 4) d.add("p2", 8)

print(d) print(d.get("p2")) // row 10 in the source

`

The error is in the row: print(d.get("p2"))

I expected that it will print 8, but:

dictionary.lobster(56): error: return requires type int?, got bool in p4.lobster(10): get(this:dictionary<string, int>, key:string)->int?

[aardappel]

Well, get has 2 forms, the one with 1 arg (which you're using) only works for nillable types, e.g. references, which will return nil if the item can't be retrieved.

But you're using int, which means you need to use the 2 argument version and specify a sentinel value, e.g. 0 or -1, to indicate no element found: d.get("p2", 0) returns 8 as expected, d.get("p3", 0) will return 0.

That said, the error is pretty bad, I will look into if that can be improved. It should ideally never even allow int?.

[milen-prg]

I think, I understand. So the one argument get() function will work only with string values (I did not succeed to make another nillable type as string?): `

let c = dictionary<string, string>{size: 5}

c.add("p1", "eeeeeee") print(c.get("p1")) `

For class/struct values must use 2 argument get() with default value?

P. S. I have some C and Python background, but no experience with 3D programming and start to learn the LOBSTER as it has amazing specifications. But, may be, because I have no experience with multimedia (especially opengl, shaders, etc.), for me it is difficult to easy learn some functions operations. Because, the Lobster is for "beginner enthusiasts in game programming", may be It will be fare more useful to have some super simple and short explanations and function examples for some not trivial functions (can be as comment in the source). For example, I yet have problem to understand:

• how to use protect/finally function in the module exception.lobster (with try/catch I succeed)
• I can't understand why the cubes in cgtest.lobster sample looks with not right angles (even I choose not flat, but phong shader, which smooths the cubes walls) and how the function cg_set() works so to generate new cube.
• May be I'm at the beginning, may be I'm until now was too far from the 3D programming, but I have many learning difficulties, as how to change the gl_unit_cube() color, etc., etc. I apologize for frankness, again - may be I'm too novice in this area, but I need some more information, as I see that there are no so simple and popular tutorial about shaders etc. in whole internet.

[aardappel]

I recommend reading the language reference and the rest of the docs on what types there are to get more clarity on how this works.

It generally is hard to write docs and provide samples for every level of background, as every person misses something different. If I had "easier" rendering functions, then they'd likely be super limiting, or a different set of people would be confused about them.

And we do have some very easy functions, if you restrict yourself to drawing colored 2D lines, rectangles etc.. no shaders needed. Even text and textures can be done with no shaders. I suggest you either stick to that, or invest the the time learn more.

In the end I can't cater to everyone, and more general rendering in Lobster does require understanding of OpenGL/GPU basics.