Question

我正在研究swift-package-manager/Documentation/Usage.md

中的第一个例子

我的设置：macOS 10.12.1，Brew（jpeg-8d和jasper-1.900.21），Swift 3.0.1

说明中未提及example/Package.swift需要此行或不会构建：
name: "example", 错误是：

/Users/yost/p/swift/package-example/work/example/Package.swift:3:22: error: missing argument for parameter 'name' in call
let package = Package(
                     ^
PackageDescription.Package:18:12: note: 'init(name:pkgConfig:providers:targets:dependencies:exclude:)' declared here
    public init(name: String, pkgConfig: String? = default, providers: [PackageDescription.SystemPackageProvider]? = default, targets: [PackageDescription.Target] = default, dependencies: [PackageDescription.Package.Dependency] = default, exclude: [String] = default)
           ^
Can't parse Package.swift manifest file because it contains invalid format. Fix Package.swift file format and try again.
error: invalid manifest format

这不在说明中，但根据本文件的Reference部分，我添加了行
providers: [ .Brew("jpeg") ]
到CJPEG/Package.swift并尝试在未安装jpeg的情况下进行构建，swift build未建议运行
brew install jpeg
因为它应该。我做了brew install jpeg并继续前进。

现在安装了jpeg brew，swift build出现了这些错误：

Compile Swift Module 'example' (1 sources)
<module-includes>:1:9: note: in file included from <module-includes>:1:
#import "/usr/local/include/jpeglib.h"
        ^
/usr/local/include/jpeglib.h:755:3: error: unknown type name 'size_t'
  size_t free_in_buffer;        /* # of byte spaces remaining in buffer */
  ^
... blah blah ...
<unknown>:0: error: build had 1 command failures
error: exit(1): /Library/Developer/Toolchains/swift-3.0-RELEASE.xctoolchain/usr/bin/swift-build-tool -f /Users/yost/p/swift/package-example/example/.build/debug.yaml

我发现我必须编辑/usr/local/include/jpeglib.h才能添加
#include <stdio.h>
在顶部。

BTW，CJPEG/module.modulemap文件说：
header "/usr/include/jpeglib.h"
jpeglib.h文件位于/usr/local/include，而不是/usr/include。为什么这不会导致构建错误？

无论如何，此时swift build出现了这些构建错误：

Compile Swift Module 'example' (1 sources)
Linking ./.build/debug/example
ld: library not found for -ljpeg for architecture x86_64
<unknown>:0: error: link command failed with exit code 1 (use -v to see invocation)
<unknown>:0: error: build had 1 command failures
error: exit(1): /Library/Developer/Toolchains/swift-3.0-RELEASE.xctoolchain/usr/bin/swift-build-tool -f /Users/yost/p/swift/package-example/example/.build/debug.yaml

我发现我不能只用以下方式构建：
swift build
我必须建立与 swift build -Xlinker -L/usr/local/include

这些调整让我了解了jpeglib示例。

当构建JasPer示例时，我收到了以下错误：

Compile Swift Module 'example' (1 sources)
<module-includes>:1:9: note: in file included from <module-includes>:1:
#import "/usr/local/include/jasper/jasper.h"
        ^
/usr/local/include/jasper/jasper.h:65:10: error: 'jasper/jas_config.h' file not found
#include <jasper/jas_config.h>
         ^
/Users/yost/p/swift/package-example/example/Sources/main.swift:3:8: error: could not build Objective-C module 'CJasPer'
import CJasPer
       ^
<unknown>:0: error: build had 1 command failures
error: exit(1): /Library/Developer/Toolchains/swift-3.0-RELEASE.xctoolchain/usr/bin/swift-build-tool -f /Users/yost/p/swift/package-example/example/.build/debug.yaml

感谢Vadim的回答，我现在知道我必须建立起来 swift build -Xcc -I/usr/local/include -Xlinker -L/usr/local/lib

但我还没有看到我可以添加到Package.swift的内容，以便我可以简单地使用
构建 swift build

Answer 1

SwiftPM更新了文档，更好地解释了系统包和一个新的例子。

https://github.com/apple/swift-package-manager/blob/master/Documentation/Usage.md#require-system-libraries

Answer 2

是-Xcc -I/usr/local/include -Xlinker -L/usr/local/lib。

请注意，为了使用不带参数的swift build，您可以为您的库指定pkgConfig property，如果它们有pkg-config utility的.pc条目。

Answer 3

SwiftPM团队扩展了Swift Packages文档并修复了很多问题（正如Ankit Agarwal所说）。

试图让swift包示例工作

3 个答案: