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<DIV id=idOWAReplyText78039 dir=ltr>
<DIV dir=ltr><FONT face="Courier New" color=#000000 size=2>Hi,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>the main "problem" is of course
that record-field names are</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>not available in run-time, unless
*you* store them some place.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>The nice rr functionality in the
shell then of course reads</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>a record definition and stores it
"somewhere", available to</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>the shell process. And then formats
any tuple suspected of</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>being that record accordingly
instead of plain tuple format.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>What you want to do is pretty
simple to accomplish in your</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>own program. But you must have
run-time access to field-names</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>and their respective location. This
can of course be done by</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>using standard record constructs
such as record_info(fields,RecordType)</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>(which in compile time will expand
to the list of all fields</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>in their correct
order).</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>I would make a function which
returns a string looking like</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>a record
(#myrecord{field1=foo,field2=bar}) and then call</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New"
size=2>io:format("~s",[record2string(Record,record_info(fields,myrecord))])</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Since the record_info construct
will expand to a list in compile</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>time. It might be of interest, if
.beam sizes is of importance</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>and their will be a lot of calls to
record2string/2,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>to make a more clever record2string
function which instead</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>has all record-field lists expanded
once and for all, taking</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>just the record-type as
argument.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" color=#000000 size=2>Best
Regards,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Lennart</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr> </DIV></DIV>
<DIV id=idSignature76725 dir=ltr>
<DIV><FONT face="Courier New" color=#000000
size=2>-------------------------------------------------------------</FONT></DIV>
<DIV><FONT face="Courier New" color=#000000 size=2>Lennart
Ohman
phone : +46-8-587 623 27</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sjöland & Thyselius Telecom
AB cellular: +46-70-552 6735</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sehlstedtsgatan
6
fax : +46-8-667 8230</FONT></DIV>
<DIV><FONT face="Courier New" size=2>SE-115 28 STOCKHOLM,
SWEDEN email : <A
href="mailto:lennart.ohman@st.se">lennart.ohman@st.se</A></FONT></DIV></DIV>
<DIV dir=ltr><BR>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>Från:</B> owner-erlang-questions@erlang.org genom
Mikael Karlsson<BR><B>Skickat:</B> on 2005-08-10 08:22<BR><B>Till:</B>
erlang-questions@erlang.org<BR><B>Ämne:</B> pretty printing of
records<BR></FONT><BR></DIV>
<DIV>
<P><FONT size=2>I have noticed the nice erlang shell commands rr() and
rp()<BR>to display records with attribute names and all.<BR>Is there a way to do
something similar directly from a<BR>program, using io:format("..",[Record]) for
instance?<BR><BR>Mikael<BR><BR></FONT></P></DIV>
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