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Append a record to the end of a text file: Difference between revisions
Append a record to the end of a text file (view source)
Revision as of 12:08, 2 July 2022
, 1 year agoAdded a Scheme implementation.
m (→{{header|Phix}}: added syntax colouring, marked p2js incompatible) |
(Added a Scheme implementation.) |
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Line 4,169:
}
} // 57 lines</lang>
=={{header|Scheme}}==
{{works with|Chez Scheme}}
<lang scheme>; Join list of strings into single string, with given separator between elements.
(define string-join
(lambda (str-lst sep)
(fold-right (lambda (ele acc) (if (string=? acc "") ele (string-append ele sep acc)))
""
str-lst)))
; Define the output file name and the three records to write to it.
(let ((filename
"mimic-passwd.txt")
(record1
(string-join
(list
"jsmith" "x" "1001" "1000"
(string-join
'("Joe Smith" "Room 1007" "(234)555-8917" "(234)555-0077" "jsmith@rosettacode.org")
",")
"/home/jsmith" "/bin/bash")
":"))
(record2
(string-join
(list
"jdoe" "x" "1002" "1000"
(string-join
'("Jane Doe" "Room 1004" "(234)555-8914" "(234)555-0044" "jdoe@rosettacode.org")
",")
"/home/jdoe" "/bin/bash")
":"))
(record3
(string-join
(list
"xyz" "x" "1003" "1000"
(string-join
'("X Yz" "Room 1003" "(234)555-8913" "(234)555-0033" "xyz@rosettacode.org")
",")
"/home/xyz" "/bin/bash")
":")))
; Write the first two records to the output file.
; Replace any existing file. Lock file for exclusive access.
(let ((op (open-file-output-port filename
(file-options replace exclusive)
'line
(make-transcoder (latin-1-codec) 'lf))))
(format op "~a~%" record1)
(format op "~a~%" record2)
(close-output-port op))
; Append the third record to the output file.
; Open existing file keeping contents. Append to file. Lock file for exclusive access.
(let ((op (open-file-output-port filename
(file-options no-fail no-truncate append exclusive)
'line
(make-transcoder (latin-1-codec) 'lf))))
(format op "~a~%" record3)
(close-output-port op)))</lang>
{{out}}
<pre>
jsmith:x:1001:1000:Joe Smith,Room 1007,(234)555-8917,(234)555-0077,jsmith@rosettacode.org:/home/jsmith:/bin/bash
jdoe:x:1002:1000:Jane Doe,Room 1004,(234)555-8914,(234)555-0044,jdoe@rosettacode.org:/home/jdoe:/bin/bash
xyz:x:1003:1000:X Yz,Room 1003,(234)555-8913,(234)555-0033,xyz@rosettacode.org:/home/xyz:/bin/bash
</pre>
{|class="wikitable" style="text-align: center; margin: 1em auto 1em auto;"
|+ Append Capabilities.
|-
!colspan=2| Data Representation
!rowspan=2| IO<BR>Library
!rowspan=2| Append<BR>Possible
!rowspan=2| Automatic<BR>Append
!rowspan=2| Multi-tasking<BR>Safe
|-
! In core || On disk
|-
| lists || text file || built-in || ☑ || ☑ || ☑ (system dependent)
|}
=={{header|Sidef}}==
| |||