英文:
how to understand golang "non-Separator characters" at path.Match
问题
当我使用golang的embed包时，我对路径匹配感到困惑。*代表什么？
官方称之为非分隔符字符
在这里：https://pkg.go.dev/path/filepath#Match
'*'匹配任何非分隔符字符的序列
起初，我理解为非分隔符字符指的是正斜杠（前导斜杠/），但下面的示例表明情况并非如此。
# 目录树
├── stubs
│ ├── hello.txt
│ └── xyz
│ └── zyx.txt
└── hello.go
# hello.go的源文件
package main
import "embed"
//go:embed stubs/*
var T1 embed.FS
//go:embed stubs*
var T2 embed.FS
func main() {
s, e := T1.ReadFile("stubs/hello.txt")
fmt.Println(string(s))
fmt.Println(e)
s, e = T2.ReadFile("stubs/xyz/zyx.txt")
fmt.Println(string(s))
fmt.Println(e)
}
然后运行go run hello.go将成功执行。
这个例子告诉我*可以匹配/。
非分隔符字符是什么意思？
感谢解释。
英文:
When I use golang's embed package, I encounter confusion about path matching. that's what * refers to?
Officially called non-Separator characters
Here: https://pkg.go.dev/path/filepath#Match
'*' matches any sequence of non-Separator characters
At first I understood non-Separator characters meant forward slashes(leading slash /), but the following example shows that this is not the case.
# dir tree
├── stubs
│   ├── hello.txt
│   └── xyz
│   └── zyx.txt
└── hello.go
# source file for hello.go
package main
import "embed"
//go:embed stubs/*
var T1 embed.FS
//go:embed stubs*
var T2 embed.FS
func main() {
s, e := T1.ReadFile("stubs/hello.txt")
fmt.Println(string(s))
fmt.Println(e)
s, e = T2.ReadFile("stubs/xyz/zyx.txt")
fmt.Println(string(s))
fmt.Println(e)
}
Then run go run hello.go will execute successfully.
This case tell me * can match /.
what does non-Separator characters mean?
Thanks for the explanation.
答案1
得分: 1
T2.ReadFile("stubs/xyz/zyx.txt")的工作原理与你想的不同。
go:embed的文档解释如下：
如果模式指定一个目录，那么以该目录为根的子树中的所有文件都会被嵌入（递归地），但以'.'或'_'开头的文件会被排除。
https://pkg.go.dev/embed#hdr-Directives
你将T2声明为：
//go:embed stubs*
var T2 embed.FS
模式stubs*匹配目录stubs，所以整个目录stubs，包括其中的所有文件（递归地），都会被包含在T2文件系统中。
英文:
T2.ReadFile("stubs/xyz/zyx.txt") works for a different reason than you think.
The documentation for go:embed explains:
> If a pattern names a directory, all files in the subtree rooted at
> that directory are embedded (recursively), except that files with
> names beginning with ‘.’ or ‘_’ are excluded.
https://pkg.go.dev/embed#hdr-Directives
You have declared T2 as:
//go:embed stubs*
var T2 embed.FS
The pattern stubs* matches the directory stubs, so the whole directory stubs, including all files in it (recursively) are included in the T2 filesystem.
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