io

Structured file parsing beyond the built-in read and write.

Import with use io. Provides structured file parsing beyond the built-in read[path] and write[path, content].

Function	Description	Example
csv[path]	Parse CSV — a file, a URL or an S3 object — into array of maps (error-value on failure)	Structured files: use io · The standard library's layer: use sys
lines[path]	Read a file, a URL or an S3 object as array of lines (error-value on failure); a file is read a block at a time (sys.file_lines), so its whole text is not held beside its lines	Structured files: use io · The standard library's layer: use sys

Note: Basic file I/O (read[path], write[path, content]) are builtins available without any import. The io module adds structured parsing only.

use io

write['/tmp/data.csv', 'name,age\nalice,30\nbob,25\n']

rows = csv['/tmp/data.csv']
log[len[rows]]         --- 2
log[rows[0].name]      --- alice
log[rows[0].age]       --- 30

ls = lines['/tmp/data.txt']
log[len[ls]]           --- number of lines
log[ls[0]]             --- first line

--- error handling
bad = csv['/tmp/missing.csv']
log[bad.ok]            --- false
log[bad.reason]        --- error message

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