Ruby input/output: Difference between revisions
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</source> | </source> | ||
</blockquote><!-- stdin stdout stderr --> | </blockquote><!-- stdin stdout stderr --> | ||
= file-like objects = | |||
<blockquote> | |||
<syntaxhighlight lang="ruby"> | |||
fd = StringIO.new("a\nb\nc") | |||
fd.seek(0) | |||
fd.readlines | |||
</syntaxhighlight> | |||
</blockquote><!-- file-like objects --> | |||
= pipes = | |||
<blockquote> | |||
<syntaxhighlight lang="ruby"> | |||
r_pipe, w_pipe = IO.pipe | |||
</syntaxhighlight> | |||
</blockquote><!-- pipes --> | |||
= files = | = files = | ||
| Line 41: | Line 57: | ||
Dir.exist?('/directory') # directory exists | Dir.exist?('/directory') # directory exists | ||
File.exists?('/file.txt') # file exists | File.exists?('/file.txt') # file exists | ||
</source> | </source> | ||
</blockquote><!-- files --> | </blockquote><!-- files --> | ||
Latest revision as of 15:49, 25 January 2023
printing
puts (print with newline)
puts "hello"print (print w/o newline)
print "a", "b", 12printf
printf "num: %5.2f name: %s", 1.123, "alex" #> "num: 1.12 name: alex"
input
line = gets puts line
stdin/stdout/stderr
ARGF # stdin
file-like objects
fd = StringIO.new("a\nb\nc") fd.seek(0) fd.readlines
pipes
r_pipe, w_pipe = IO.pipe
files
File.open('/var/tmp/file.txt', 'a') do |fd| fd.write("foo") end Dir.exist?('/directory') # directory exists File.exists?('/file.txt') # file exists
