Difference between revisions of "Io.lines"
From GiderosMobile
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__NOTOC__ | __NOTOC__ | ||
| − | + | '''Available since:''' Gideros 2011.6<br/> | |
| − | ''' | + | '''Class:''' [[io]]<br/> |
| − | ''' | ||
| − | |||
| − | |||
| − | + | === Description === | |
| + | Opens the given file name in read mode and returns an iterator function. Each time the iterator function is called, it returns a new line from the file. | ||
| + | <source lang="lua"> | ||
| + | (function) = io.lines(filename) | ||
| + | </source> | ||
| − | |||
| + | The construction | ||
| + | <source lang="lua"> | ||
| + | for line in io.lines(filename) do body end | ||
| + | </source> | ||
| + | will iterate over all lines of the file. When the iterator function detects the end of file, it returns nil (to finish the loop) and automatically closes the file. | ||
| − | + | The call '''io.lines()''' (with no file name) is equivalent to '''io.input():lines()''' that is, it iterates over the lines of the default input file. In this case it does not close the file when the loop ends. | |
| + | |||
| + | === Parameters === | ||
| + | '''filename''': (string) filename to open '''optional'''<br/> | ||
| + | |||
| + | === Return values === | ||
| + | '''Returns''' (function) iterator function<br/> | ||
| + | |||
| + | === Example === | ||
| + | '''Iterates over all lines of a file''' | ||
<source lang="lua"> | <source lang="lua"> | ||
| − | + | for line in io.lines(filename) do | |
| + | -- do stuff | ||
| + | end | ||
</source> | </source> | ||
| − | |||
| − | |||
| − | |||
| − | |||
{{Io}} | {{Io}} | ||
Revision as of 05:00, 7 December 2020
Available since: Gideros 2011.6
Class: io
Description
Opens the given file name in read mode and returns an iterator function. Each time the iterator function is called, it returns a new line from the file.
(function) = io.lines(filename)
The construction
for line in io.lines(filename) do body end
will iterate over all lines of the file. When the iterator function detects the end of file, it returns nil (to finish the loop) and automatically closes the file.
The call io.lines() (with no file name) is equivalent to io.input():lines() that is, it iterates over the lines of the default input file. In this case it does not close the file when the loop ends.
Parameters
filename: (string) filename to open optional
Return values
Returns (function) iterator function
Example
Iterates over all lines of a file
for line in io.lines(filename) do
-- do stuff
end
