Re: XML module question?

[Bruce Gray]

> On Jul 15, 2021, at 11:02 PM, William Michels via perl6-users 
>  wrote:

(and I re-ordered):

> Any help appreciated,
> Thanks, Bill.
> REFERENCE:  https://unix.stackexchange.com/q/166675/227738


> I'm trying to put an answer together for SO, and I keep running into the same 
> difficulty. Given a CSV file,

Note: input is a log file, not in CSV format.

> how can one produce an XML file with latitude and longitude values properly 
> quoted? Every time I get proper quoting, "lat" and "lon" are scrambled (i.e. 
> sometimes "lat" first, sometimes "lat" second). 
...
> using the "make-xml()" function from the XML module, I end up scrambling 
> "lat/lon”:

You are using the correct XML module, and you are using it correctly.

Similar to a Raku hash, the attributes in an XML start-tag are *unordered*.
While the inconsistant ordering may be displeasing to our human eyes, any 
program reading XML should treat your current output identically to your 
desired output.

In Raku-speak, these two hashes have the same contents:
my %wpt1 = lat => 'A', lon => 'z';
my %wpt2 = lon => 'z', lat => 'A’;

Designers of XML libraries are reluctant to add the ability to force an 
ordering; it would lead to XML-reading programs making improper assumptions.
Like many major XML libraries in other languages, I see no such ability in the 
Raku XML module.
See:
https://www.w3.org/TR/REC-xml/#sec-starttags
Note that the order of attribute specifications
in a start-tag or empty-element tag is not significant.

https://stackoverflow.com/questions/57756005/writing-xml-attributes-and-namespace-declarations-in-a-specific-order

https://community.adobe.com/t5/coldfusion/maintain-attribute-order-in-xml-with-a-structure/m-p/3838398

> Conversely, if I manage to restrict "lat/lon" to the correct order, I lose 
> the equals sign and proper (value) quotation.


Unless you just hardcode a template and insert the lat/lon/datetime values 
(never a good idea), you will have to live with the varying order.
I will point out that the XML library also does not output the multi-line 
indentation that the OP shows; it is irrelevant in XML.


> $ raku -MXML -e 'my @xml = do for lines() {make-xml("wpt", 
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put 
> for @xml;’  lat_lon.txt

Minor critiques:
That use of `@array = do for lines() {…}` is more commonly written as `@array = 
lines().map: {…}`
raku -MXML -e 'my @xml = lines().map: {make-xml("wpt", 
:lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put for 
@xml;'  lat_lon.txt

Nothing is gained by creating an array, just to print each line of the array, 
so your can just `put` each time you construct an XML line.
raku -MXML -e 'for lines() { put make-xml("wpt", 
:lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2])) }'  
lat_lon.txt

When all the output is per-line based on the input, the `-p` or `-n` flag 
removes the need for `for lines`.
raku -MXML -ne 'put make-xml("wpt", :lat(.words[5].subst(";")), 
:lon(.words[8]), \("time",.words[0..2]))'  lat_lon.txt



> So far, I can correctly swap the date/time to the end:
> 
> $ raku -MXML -e 'my @reordered = do for lines() 
> {(.words[3..*],.words[0..2])}; .put for @reordered;’  lat_lon.txt

I am sure that `-MXML` is leftover from other experiments.
Removing `@reordered` and switching to `-n` like my critiques above, this 
becomes:
raku -ne 'put (.words[3..*],.words[0..2]);' lat_lon.txt
To “wow” the SO crowd, you might note that @array[N..*],@array[0..N-1] has a 
shortcut in Raku (.rotate), making this the tightest of all the solutions I see 
so far:
raku -ne 'put .words.rotate(3);'  lat_lon.txt

-- 
Hope this helps,
Bruce Gray (Util of PerlMonks)

Re: XML module question?

[David Warring]

The XML::Writer  module side-steps any
ordering issues by directly serializing data structures to xml:

$ raku -M XML::Writer -e'say XML::Writer.serialize: :wpt[ :lat<42>,
:long<69>, "blah" ]'
blah

On Sat, Jul 17, 2021 at 4:48 AM Bruce Gray 
wrote:

> > On Jul 15, 2021, at 11:02 PM, William Michels via perl6-users <
> perl6-us...@perl.org> wrote:
>
> (and I re-ordered):
>
> > Any help appreciated,
> > Thanks, Bill.
> > REFERENCE:  https://unix.stackexchange.com/q/166675/227738
>
>
> > I'm trying to put an answer together for SO, and I keep running into the
> same difficulty. Given a CSV file,
>
> Note: input is a log file, not in CSV format.
>
> > how can one produce an XML file with latitude and longitude values
> properly quoted? Every time I get proper quoting, "lat" and "lon" are
> scrambled (i.e. sometimes "lat" first, sometimes "lat" second).
> ...
> > using the "make-xml()" function from the XML module, I end up scrambling
> "lat/lon”:
>
> You are using the correct XML module, and you are using it correctly.
>
> Similar to a Raku hash, the attributes in an XML start-tag are *unordered*.
> While the inconsistant ordering may be displeasing to our human eyes, any
> program reading XML should treat your current output identically to your
> desired output.
>
> In Raku-speak, these two hashes have the same contents:
> my %wpt1 = lat => 'A', lon => 'z';
> my %wpt2 = lon => 'z', lat => 'A’;
>
> Designers of XML libraries are reluctant to add the ability to force an
> ordering; it would lead to XML-reading programs making improper assumptions.
> Like many major XML libraries in other languages, I see no such ability in
> the Raku XML module.
> See:
> https://www.w3.org/TR/REC-xml/#sec-starttags
> Note that the order of attribute specifications
> in a start-tag or empty-element tag is not significant.
>
> https://stackoverflow.com/questions/57756005/writing-xml-attributes-and-namespace-declarations-in-a-specific-order
>
> https://community.adobe.com/t5/coldfusion/maintain-attribute-order-in-xml-with-a-structure/m-p/3838398
>
> > Conversely, if I manage to restrict "lat/lon" to the correct order, I
> lose the equals sign and proper (value) quotation.
>
>
> Unless you just hardcode a template and insert the lat/lon/datetime values
> (never a good idea), you will have to live with the varying order.
> I will point out that the XML library also does not output the multi-line
> indentation that the OP shows; it is irrelevant in XML.
>
>
> > $ raku -MXML -e 'my @xml = do for lines() {make-xml("wpt",
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put
> for @xml;’  lat_lon.txt
>
> Minor critiques:
> That use of `@array = do for lines() {…}` is more commonly written as
> `@array = lines().map: {…}`
> raku -MXML -e 'my @xml = lines().map: {make-xml("wpt",
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put
> for @xml;'  lat_lon.txt
>
> Nothing is gained by creating an array, just to print each line of the
> array, so your can just `put` each time you construct an XML line.
> raku -MXML -e 'for lines() { put make-xml("wpt",
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2])) }'
> lat_lon.txt
>
> When all the output is per-line based on the input, the `-p` or `-n` flag
> removes the need for `for lines`.
> raku -MXML -ne 'put make-xml("wpt", :lat(.words[5].subst(";")),
> :lon(.words[8]), \("time",.words[0..2]))'  lat_lon.txt
>
>
>
> > So far, I can correctly swap the date/time to the end:
> >
> > $ raku -MXML -e 'my @reordered = do for lines()
> {(.words[3..*],.words[0..2])}; .put for @reordered;’  lat_lon.txt
>
> I am sure that `-MXML` is leftover from other experiments.
> Removing `@reordered` and switching to `-n` like my critiques above, this
> becomes:
> raku -ne 'put (.words[3..*],.words[0..2]);' lat_lon.txt
> To “wow” the SO crowd, you might note that @array[N..*],@array[0..N-1] has
> a shortcut in Raku (.rotate), making this the tightest of all the solutions
> I see so far:
> raku -ne 'put .words.rotate(3);'  lat_lon.txt
>
> --
> Hope this helps,
> Bruce Gray (Util of PerlMonks)
>
>

Re: XML module question?

[Bruce Gray]

David,

Aha! I am very glad to be wrong!

$ raku -MXML::Writer -ne 'print XML::Writer.serialize: :wpt[ 
:lat(.words[5].subst(";")), :lon(.words[8]), :time[.words.head(3).join(" ")] 
];'  lat_lon.txt
11-06-2014 - 10:49:06PM
11-06-2014 - 10:49:49PM
11-06-2014 - 10:50:35PM
11-06-2014 - 10:51:21PM
11-06-2014 - 10:52:08PM
11-06-2014 - 10:53:30PM
11-06-2014 - 10:54:50PM

I do note that XML::Writer does not show up in the search at 
https://modules.raku.org/t/XML ,
and is very under-documented, so that is an opportunity for someone to 
contribute.

-- 
Hope this helps,
Bruce Gray (Util of PerlMonks)

> On Jul 16, 2021, at 2:53 PM, David Warring  wrote:
> 
> The XML::Writer module side-steps any ordering issues by directly serializing 
> data structures to xml:
> 
> $ raku -M XML::Writer -e'say XML::Writer.serialize: :wpt[ :lat<42>, 
> :long<69>, "blah" ]'
> blah
> 
> On Sat, Jul 17, 2021 at 4:48 AM Bruce Gray  wrote:
> > On Jul 15, 2021, at 11:02 PM, William Michels via perl6-users 
> >  wrote:
> 
> (and I re-ordered):
> 
> > Any help appreciated,
> > Thanks, Bill.
> > REFERENCE:  https://unix.stackexchange.com/q/166675/227738
> 
> 
> > I'm trying to put an answer together for SO, and I keep running into the 
> > same difficulty. Given a CSV file,
> 
> Note: input is a log file, not in CSV format.
> 
> > how can one produce an XML file with latitude and longitude values properly 
> > quoted? Every time I get proper quoting, "lat" and "lon" are scrambled 
> > (i.e. sometimes "lat" first, sometimes "lat" second). 
> ...
> > using the "make-xml()" function from the XML module, I end up scrambling 
> > "lat/lon”:
> 
> You are using the correct XML module, and you are using it correctly.
> 
> Similar to a Raku hash, the attributes in an XML start-tag are *unordered*.
> While the inconsistant ordering may be displeasing to our human eyes, any 
> program reading XML should treat your current output identically to your 
> desired output.
> 
> In Raku-speak, these two hashes have the same contents:
> my %wpt1 = lat => 'A', lon => 'z';
> my %wpt2 = lon => 'z', lat => 'A’;
> 
> Designers of XML libraries are reluctant to add the ability to force an 
> ordering; it would lead to XML-reading programs making improper assumptions.
> Like many major XML libraries in other languages, I see no such ability in 
> the Raku XML module.
> See:
> https://www.w3.org/TR/REC-xml/#sec-starttags
> Note that the order of attribute specifications
> in a start-tag or empty-element tag is not significant.
> 
> https://stackoverflow.com/questions/57756005/writing-xml-attributes-and-namespace-declarations-in-a-specific-order
> 
> https://community.adobe.com/t5/coldfusion/maintain-attribute-order-in-xml-with-a-structure/m-p/3838398
> 
> > Conversely, if I manage to restrict "lat/lon" to the correct order, I lose 
> > the equals sign and proper (value) quotation.
> 
> 
> Unless you just hardcode a template and insert the lat/lon/datetime values 
> (never a good idea), you will have to live with the varying order.
> I will point out that the XML library also does not output the multi-line 
> indentation that the OP shows; it is irrelevant in XML.
> 
> 
> > $ raku -MXML -e 'my @xml = do for lines() {make-xml("wpt", 
> > :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put 
> > for @xml;’  lat_lon.txt
> 
> Minor critiques:
> That use of `@array = do for lines() {…}` is more commonly written as `@array 
> = lines().map: {…}`
> raku -MXML -e 'my @xml = lines().map: {make-xml("wpt", 
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2]))}; .put 
> for @xml;'  lat_lon.txt
> 
> Nothing is gained by creating an array, just to print each line of the array, 
> so your can just `put` each time you construct an XML line.
> raku -MXML -e 'for lines() { put make-xml("wpt", 
> :lat(.words[5].subst(";")), :lon(.words[8]), \("time",.words[0..2])) }'  
> lat_lon.txt
> 
> When all the output is per-line based on the input, the `-p` or `-n` flag 
> removes the need for `for lines`.
> raku -MXML -ne 'put make-xml("wpt", :lat(.words[5].subst(";")), 
> :lon(.words[8]), \("time",.words[0..2]))'  lat_lon.txt
> 
> 
> 
> > So far, I can correctly swap the date/time to the end:
> > 
> > $ raku -MXML -e 'my @reordered = do for lines() 
> > {(.words[3..*],.words[0..2])}; .put for @reordered;’  lat_lon.txt
> 
> I am sure that `-MXML` is leftover from other experiments.
> Removing `@reordered` and switching to `-n` like my critiques above, this 
> becomes:
> raku -ne 'put (.words[3..*],.words[0..2]);' lat_lon.txt
> To “wow” the SO crowd, you might note that @array[N..*],@array[0..N-1] has a 
> shortcut in Raku (.rotate), making this the tightest of all the solutions I 
> see so far:
> raku -ne 'put .words.rotate(3);'  lat_lon.txt
> 
> -- 
> Hope this helps,
> Bruce Gray (Util of PerlMonks)
>