How to read lines from stdin (*in*) in clojure

Question

I am writing my first clojure program, and want to read lines from stdin. When I try this: ``` (doall (map #(println %) (line-seq *in*))) ``` I get this exception: ``` Exception in thread "main" java.lang.ClassCastException: clojure.lang.LineNumberingPushbackReader cannot be cast to java.io.BufferedReader (test.clj:0) ``` I get the same results in version 1.0 and 1.1 So how do I convert `*in*` into a seq I can iterate over? I would have thought that this is common enough that `*in*` itself would be iterable, but that does not work either - if I try to use it directly I get: ``` java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.LineNumberingPushbackReader (NO_SOURCE_FILE:0) ``` Also, are there any examples of doing general file handling in clojure?

Accepted Answer

Try wrapping `*in*` in a `java.io.BufferedReader`. And also use `doseq` instead of `doall`, as devstopfix pointed out:

```
(doseq [ln (line-seq (java.io.BufferedReader. *in*))]
   (println ln))
```

Note that `line-seq` is documented to require a `BufferedReader` as its source.

How to read lines from stdin (in) in clojure

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