Sema

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File I/O & Paths ​

Console I/O ​

display ​

Print a value without a trailing newline.

scheme
(display "no newline")
(display 42)

println ​

Print a value followed by a newline.

scheme
(println "with newline")
(println 42)

print ​

Alias for display. Print without a trailing newline.

scheme
(print "also no newline")

newline ​

Print a newline character.

scheme
(newline)

read-line ​

Read a line of input from stdin.

scheme
(define name (read-line))

File Operations ​

file/read ​

Read the entire contents of a file as a string.

scheme
(file/read "data.txt")   ; => "file contents..."

file/write ​

Write a string to a file, overwriting any existing content.

scheme
(file/write "out.txt" "content")

file/append ​

Append a string to a file.

scheme
(file/append "log.txt" "new line\n")

file/read-lines ​

Read a file as a list of lines.

scheme
(file/read-lines "data.txt")   ; => ("line 1" "line 2" "line 3")

file/write-lines ​

Write a list of strings to a file, one per line.

scheme
(file/write-lines "out.txt" '("a" "b" "c"))

file/delete ​

Delete a file.

scheme
(file/delete "tmp.txt")

file/rename ​

Rename or move a file.

scheme
(file/rename "old.txt" "new.txt")

file/copy ​

Copy a file.

scheme
(file/copy "src.txt" "dst.txt")

File Predicates ​

file/exists? ​

Test if a file or directory exists.

scheme
(file/exists? "data.txt")   ; => #t or #f

file/is-file? ​

Test if a path is a regular file.

scheme
(file/is-file? "data.txt")   ; => #t

file/is-directory? ​

Test if a path is a directory.

scheme
(file/is-directory? "src/")   ; => #t

Test if a path is a symbolic link.

scheme
(file/is-symlink? "link")   ; => #t or #f

Directory Operations ​

file/list ​

List entries in a directory.

scheme
(file/list "src/")   ; => ("main.rs" "lib.rs" ...)

file/mkdir ​

Create a directory.

scheme
(file/mkdir "new-dir")

file/info ​

Get file metadata. Returns a map with :size, :modified, and other keys.

scheme
(file/info "data.txt")   ; => {:size 1234 :modified 1707955200 ...}

Path Manipulation ​

path/join ​

Join path components.

scheme
(path/join "src" "main.rs")   ; => "src/main.rs"
(path/join "a" "b" "c.txt")  ; => "a/b/c.txt"

path/dirname ​

Return the directory portion of a path.

scheme
(path/dirname "/a/b/c.txt")   ; => "/a/b"

path/basename ​

Return the filename portion of a path.

scheme
(path/basename "/a/b/c.txt")   ; => "c.txt"

path/extension ​

Return the file extension (without the dot).

scheme
(path/extension "file.rs")     ; => "rs"
(path/extension "Makefile")    ; => ""

path/absolute ​

Return the absolute path.

scheme
(path/absolute ".")   ; => "/full/path/to/current/dir"