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<h4 class="subsection">6.1.3 Extensions to namelist</h4>
<p><a name="index-Namelist-308"></a>
GNU Fortran fully supports the Fortran 95 standard for namelist I/O
including array qualifiers, substrings and fully qualified derived types.
The output from a namelist write is compatible with namelist read. The
output has all names in upper case and indentation to column 1 after the
namelist name. Two extensions are permitted:
<p>Old-style use of ‘<samp><span class="samp">$</span></samp>’ instead of ‘<samp><span class="samp">&</span></samp>’
<pre class="smallexample"> $MYNML
X(:)%Y(2) = 1.0 2.0 3.0
CH(1:4) = "abcd"
$END
</pre>
<p>It should be noted that the default terminator is ‘<samp><span class="samp">/</span></samp>’ rather than
‘<samp><span class="samp">&END</span></samp>’.
<p>Querying of the namelist when inputting from stdin. After at least
one space, entering ‘<samp><span class="samp">?</span></samp>’ sends to stdout the namelist name and the names of
the variables in the namelist:
<pre class="smallexample"> ?
&mynml
x
x%y
ch
&end
</pre>
<p>Entering ‘<samp><span class="samp">=?</span></samp>’ outputs the namelist to stdout, as if
<code>WRITE(*,NML = mynml)</code> had been called:
<pre class="smallexample"> =?
&MYNML
X(1)%Y= 0.000000 , 1.000000 , 0.000000 ,
X(2)%Y= 0.000000 , 2.000000 , 0.000000 ,
X(3)%Y= 0.000000 , 3.000000 , 0.000000 ,
CH=abcd, /
</pre>
<p>To aid this dialog, when input is from stdin, errors send their
messages to stderr and execution continues, even if <code>IOSTAT</code> is set.
<p><code>PRINT</code> namelist is permitted. This causes an error if
<samp><span class="option">-std=f95</span></samp> is used.
<pre class="smallexample"> PROGRAM test_print
REAL, dimension (4) :: x = (/1.0, 2.0, 3.0, 4.0/)
NAMELIST /mynml/ x
PRINT mynml
END PROGRAM test_print
</pre>
<p>Expanded namelist reads are permitted. This causes an error if
<samp><span class="option">-std=f95</span></samp> is used. In the following example, the first element
of the array will be given the value 0.00 and the two succeeding
elements will be given the values 1.00 and 2.00.
<pre class="smallexample"> &MYNML
X(1,1) = 0.00 , 1.00 , 2.00
/
</pre>
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