Skip to content

lazy+andThen+map3 overflowing the stack #9

@Janiczek

Description

@Janiczek

Use of these three (or maybe two, I'm not sure about map3) results in "too much recursion."

Ellie with a SSCCE ➡️ https://ellie-app.com/4Kv76dc7Hkpa1

type Expr
    = Int_ Int
    | Plus2 Expr Expr
    | Plus3 Expr Expr Expr


exprGenerator : Generator Expr
exprGenerator =
    Random.uniform
        (Random.map Int_ (Random.int Random.minInt Random.maxInt))
        --[ Random.map2 Plus2 lazyExprGenerator lazyExprGenerator
        [ Random.map3 Plus3 lazyExprGenerator lazyExprGenerator lazyExprGenerator
        ]
        |> Random.andThen identity


lazyExprGenerator : Generator Expr
lazyExprGenerator =
    Random.lazy (\() -> exprGenerator)

recursion

Switching the recursive generators (Plus3 for Plus2) or changing the seed to 1 shows non-failing case.

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions