Typed values

get_content and get_attribute (of xml_file and xml_index) convert text into numbers and logicals.

call case_file%get_content(id=case_file%find(path='case/time/dt'), value=dt)
call case_file%get_content(id=case_file%find(path='case/time/steps'), value=steps)
call case_file%get_content(id=case_file%find(path='case/time/adaptive'), value=adaptive)
call case_file%get_content(id=case_file%find(path='case/mesh/domain'), values=domain)
call case_file%get_attribute(id=case_file%find(name='grid'), name='ni', value=ni)
call case_file%get_attribute(id=case_file%find(name='grid'), name='nj', value=nj)

Call	Converts
get_content(id, value, [iostat=], [iomsg=])	the content of tag id (as content(id=))
get_attribute(id, name, value, [iostat=], [iomsg=])	attribute name of tag id

value is an integer (I1P, I2P, I4P, I8P), a real (R4P, R8P) or a logical (true, false, 1, 0, lowercase only: True is XML_BAD_VALUE, as in XML Schema). With values= instead, an allocatable rank-1 integer or real array, the text is a blank-separated list ("0 10 0 10 0 0") and the array gets its size.

Errors

density = 1.0_R8P                                                           ! a default, kept on error
call case_file%get_content(id=case_file%find(path='case/fluid/densty'), value=density, iostat=iostat, iomsg=iomsg)
if (iostat==XML_NOT_FOUND) print '(A,F6.3)', 'not found, density kept: ', density
call case_file%get_attribute(id=case_file%find(name='density'), name='unit', value=steps, iostat=iostat, iomsg=iomsg)
if (iostat==XML_BAD_VALUE) print '(A)', trim(iomsg)

iostat	Meaning
0	converted
XML_NOT_FOUND	the tag (id out of range, 0 included) or the attribute does not exist
XML_BAD_VALUE	not a value of that type: a character not allowed, a token not converted (e.g. out of range), not exactly one token for a scalar; iomsg quotes the token and names the tag or attribute
other	xml_index%get_content only: the I/O error reading the file

On error the scalar keeps its value and the list is empty: a default set before the call survives. An empty text is an empty list with iostat=0: check size(values) when a value is required. Without iostat errors are silent.

Each token is converted by StringiFor (string%read_number): correctly rounded, with exact range checks and without a read statement, so the results are the same with every compiler.

• Integers are digits with an optional sign, as XML integers: 1e3, 1.0 and 0x1F are XML_BAD_VALUE. A value out of the range of the kind is XML_BAD_VALUE, for every kind.
• Reals are decimal numbers with an optional exponent (e, E, d, D), Inf, Infinity and NaN (any case, with an optional sign; NaN(...) too). A real too large reads as an infinity, one too small as zero (or a subnormal).
• Separators such as , or /, quotes, repeat counts (2*5) and Fortran's exponent without a letter (1+3) are rejected, never interpreted.

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