[post] new post

content/daily/2025-01-06.md

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+title = 2025-01-06
+author = ["SouthFox"]
+date = 2025-01-06T23:33:00+08:00
+lastmod = 2025-01-06T23:45:53+08:00
+tags = ["publish"]
+draft = false
++++
+
+## Hy {#hy}
+
+[API reference — Hy 1.0.0 manual](https://hylang.org/hy/doc/v1.0.0/api#for)
+
+[hy]({{< relref "../main/20250106234212-hy.md" >}}) 里 `for` 里能引用之前的标识符，达到 `python` 里用多个 `for` 循环能表达同样的效果。
+
+```hy
+(for [[root dirs files] (os.walk "source")
+       -file files]
+    (let [file (os.path.join root -file)]
+      (when (and (in "posts" file) (file.endswith ".md"))
+        (markdown-files.append file))))
+```