elm - Elm 0.17 中的图像

Question

我正在尝试使用单个图像的测试示例:

import Html exposing (Html)
import Graphics.Element
main = image 960 500 "starry-night.jpg"

我正在使用 elm-reactor 尝试这个，但这个简单的结果无法编译:

I cannot find module 'Graphics.Element'.

Module 'Main' is trying to import it.

Potential problems could be:
  * Misspelled the module name
  * Need to add a source directory or new dependency to elm-package.json

我尝试导入必要的图形包，evancz/elm-graphics

john@me:~/Documents/Elm$ cat elm-package.json

{
    "version": "1.0.0",
    "summary": "helpful summary of your project, less than 80 characters",
    "repository": "https://github.com/user/project.git",
    "license": "BSD3",
    "source-directories": [
        "."
    ],
    "exposed-modules": [],
    "dependencies": {
        "elm-lang/core": "4.0.1 <= v < 5.0.0",
        "elm-lang/html": "1.0.0 <= v < 2.0.0",
        "elm-lang/svg": "1.0.0 <= v < 2.0.0",
        "evancz/elm-graphics": "1.0.0 <= v < 2.0.0"
    },
    "elm-version": "0.17.0 <= v < 0.18.0"
}

<小时/>

我想出了:

import Html exposing (Html)
import Element exposing (image, toHtml)
main = toHtml ( image 960 500 "starry-night.jpg" )

Answer 1

模块的名称是 Element，而不是 Graphics.Element，因此编译器无法找到它。

此外，image 函数返回一个 Element，而 main 函数需要 Html 类型的内容.

程序的运行版本可能类似于

import Element exposing (..)

main =
    toHtml (image 960 500 "starry-night.jpg")