Templates: various questions not worth their own thread

[ownedbycats]

In this specific case, the switch_if() is in #kobopath, which is called by the save template ({#kobopath:re(_,/)}/{author_sort:sublist(0,1,&)}/{title} - {authors}).

Just to be safe, I set up this template rule, so I tend to know right away that I loaded up the wrong version.

[ownedbycats]

New question:

I have a composite colum, #chapters, which formats the chapter count:

program:
	input = $#kobobookmark;
# Don't change this to 'count' as that's a function
	ccount = $$#chaptercount;

	if 
## Checks that a Fanfiction has a Kobo bookmark of the right format and is not anthology|oneshot
		$#booktype=='Fanfiction'
		&& substr(input, 0, 10) == 'OEBPS/file'
## I'm not sure why this line is backwards
		&& $#fanficstatus in 'Anthology,Oneshot'
	then
## Extracts number from bookmark, subtracts 1, and then formats them as 'currentchap/totalchap'
		strcat(format_number(re(input, '.*\/file(\d+).*', '\1') - 1, '{0:,d}'), '/',ccount)

## Display 'Not Set' if there's no chapter count
	elif
		ccount == 'None'
	then
		'Not Set'

## Display regular chapter count - ignore '1' on most books (magazines, reference books, etc)
	elif
		$#booktype=='Fanfiction'
		||ccount >#1
	then
		ccount
	fi

If the conditionals match, lines the first if-then makes a result that looks like '10/20' or '5/5.' (I use this to track how many chapters I've read in a fanfic. )

I have a stored template, fanfic_unreadchaps(), that checks the composite column and subtracts the first number from the second. 10/20 produces '10' and 5/5 produces '0.'

program:
	if '/' in $#chapters then
		f = re($#chapters, '(.*)/.*', '\1');
		s = re($#chapters, '.*/(.*)', '\1');
		(s - f)
	fi

This is used in several places; saved searches, column colour/icon rules, action chains templates.

Would performance improve much if I used something like this, that checked the relevant columns directly rather than the composite?

program:
input = $#kobobookmark;
	if 
		$#booktype == 'Fanfiction'
		&& substr(input, 0, 10) == 'OEBPS/file'
		&& !$#fanficstatus in 'Anthology,Oneshot'
	then
		currentchap = re(input, '.*\/file(\d+).*', '\1') - 1;
		totalchap = $#chaptercount;

		totalchap - currentchap
	fi

[ownedbycats]

Additionally, something I forgot: logical-and is '&&.' What is a logical-or?

EDIT: Found it in the reference. ||

ANOTHER EDIT: In the Calibre search, it's possible to do something like this to find matches in both groups:

(title:foo AND author:bar) OR (title:bar AND author:bar)

if possible, how would the same thing be done in a template?

[chaley]

Originally Posted by ownedbycats

[...]
This is used in several places; saved searches, column colour/icon rules, action chains templates.

Would performance improve much if I used something like this, that checked the relevant columns directly rather than the composite?

program:
input = $#kobobookmark;
	if 
		$#booktype == 'Fanfiction'
		&& substr(input, 0, 10) == 'OEBPS/file'
		&& !$#fanficstatus in 'Anthology,Oneshot'
	then
		currentchap = re(input, '.*\/file(\d+).*', '\1') - 1;
		totalchap = $#chaptercount;

		totalchap - currentchap
	fi

Really hard to say, as it depends on the usage pattern. When doing rules or anything else that nests composite access, the composites are evaluated once per book, then cached. The first use evaluates the composite. Second and later uses see the cached result.

If the composite is used only once then the second approach is faster because the template isn't as complicated. However, the second approach introduces maintenance problems, as you would have two (or more) places that make assumptions about column contents.

Of course, the fastest would be to use a Python template for #chapters. These are as fast as native calibre code.

Note: the composite cache is cleared whenever metadata changes. If you are using these templates in action chains where the chains alter metadata then the cache won't be as effective.

[chaley]

Originally Posted by ownedbycats

Additionally, something I forgot: logical-and is '&&.' What is a logical-or?

EDIT: Found it in the reference. ||

ANOTHER EDIT: In the Calibre search, it's possible to do something like this to find matches in both groups:

(title:foo AND author:bar) OR (title:bar AND author:bar)

if possible, how would the same thing be done in a template?

In an "if" in a template? More or less as you wrote it.

('foo' in $title && 'bar' in $author) || ('bar' in $title && 'bar' in $author)

Note that the expression can be simplified in both cases, removing the duplicate author check.

('foo' in $title || 'bar' in $title) && 'bar' in $author

(title:foo OR title:bar) AND author:bar

They both can be further simplified using regular expressions.

'foo|bar' in $title && 'bar' in $author

title:~foo|bar AND author:bar

[ownedbycats]

That works! I was able to combine two if-thens that returned the same value:

	if 
		select($identifiers, 'url') 
		&& !'Anthology' in $#fanficstatus
	then
		if 
			$publisher == 'Archive of Our Own'
			&& !select($identifiers, 'ao3')
		then 'metadata.png' 

		elif 
			$publisher == 'FanFiction.net'
			&& !select($identifiers, 'ffnet')
		then 'metadata.png' 
		fi
	fi,

into this:

	if 
		select($identifiers, 'url') 
		&& !'Anthology' in $#fanficstatus
	then
		if 					
			($publisher == 'Archive of Our Own' 
			&& !select($identifiers, 'ao3'))
			|| 
			($publisher == 'FanFiction.net' 
			&& !select($identifiers, 'ffnet'))
		then 'metadata.png' 
		fi
	fi,

[chaley]

Originally Posted by ownedbycats

That works! I was able to combine two if-thens that returned the same value:

	if 
		select($identifiers, 'url') 
		&& !'Anthology' in $#fanficstatus
	then
		if 
			$publisher == 'Archive of Our Own'
			&& !select($identifiers, 'ao3')
		then 'metadata.png' 

		elif 
			$publisher == 'FanFiction.net'
			&& !select($identifiers, 'ffnet')
		then 'metadata.png' 
		fi
	fi,

into this:

	if 
		select($identifiers, 'url') 
		&& !'Anthology' in $#fanficstatus
	then
		if 					
			($publisher == 'Archive of Our Own' 
			&& !select($identifiers, 'ao3'))
			|| 
			($publisher == 'FanFiction.net' 
			&& !select($identifiers, 'ffnet'))
		then 'metadata.png' 
		fi
	fi,

FWIW: if one of the (x && y) expressions occurs significantly more often than the other then it should be the first. The formatter does "shortcutting" where it stops evaluating when the result is known. If the first expression before the || returns true then the second expression isn't evaluated.

[ownedbycats]

Question:

Previously, in the template I have to generate Kobo collections (not composite; Action Chains single-field edit) was something like this:

if $#booktype == 'Fanfiction' then 'Fanfiction' fi,
if $#booktype == 'Fiction' then 'Fiction' fi,
if $#booktype == 'Nonfiction' then 'Nonfiction' fi,

(#booktype is enumerated)

Obviously, that could be simplified:

program:
	genre = $#subjects;

	colls = strcat(	
		$#booktype,	
		if 'overdrive' in approximate_formats() then 'Loans,' fi,
		if $$#purchasecost == '0.00' then 'Freebies,' fi,
		if '^Horses$' inlist genre then 'Horses,' fi,
		if '^Cozy Mystery$' inlist genre then 'Cozy Mysteries,' fi,
		if '^(Fantasy|Science Fiction|Paranormal)$' inlist genre then 'Fantasy & Sci-Fi,' fi,
		if 'Omnibus' in $#admintags then 'Omnibuses' fi
);

 new_colls = list_union($#kobocoll, colls, ',')

How do I get #booktype to also return a comma?

[chaley]

Originally Posted by ownedbycats

Question:
[...]

program:
	genre = $#subjects;

	colls = strcat(	
		$#booktype,	
		if 'overdrive' in approximate_formats() then 'Loans,' fi,
		if $$#purchasecost == '0.00' then 'Freebies,' fi,
		if '^Horses$' inlist genre then 'Horses,' fi,
		if '^Cozy Mystery$' inlist genre then 'Cozy Mysteries,' fi,
		if '^(Fantasy|Science Fiction|Paranormal)$' inlist genre then 'Fantasy & Sci-Fi,' fi,
		if 'Omnibus' in $#admintags then 'Omnibuses' fi
);

 new_colls = list_union($#kobocoll, colls, ',')

How do I get #booktype to also return a comma?

Add the comma to the strcat().

program:
	genre = $#subjects;

	colls = strcat(	
		$#booktype, ',',
		[...]

Don't worry about the possibility of colls ending in a comma. The list_union() will remove it.

[ownedbycats]

#kobocoll is a taglike column so I'd think it'd remove excess commas anyways. Thanks

[ownedbycats]

New question:

I created several user-categories to group the entries in taglike #fanficcat. (For several reasons, I prefer to leave the column itself as nonhierarchical entries.)


To find books that have entries not present in the categories, I search for #fanficcat:true AND @Fanfiction.Fandoms:.false. Is it possible to also check this with a template?

EDIT:

program: 
	if 
		$#fanficcat 
		&& !'Fandom' inlist user_categories() 
	then 
		'aaaa' 
	fi

[ownedbycats]

In the book list, there's a stray comma at the beginning of this composite taglike. Where is it coming from?

EDIT: It goes away if I run the strcat through list_remove_duplicates.

[isarl]

Originally Posted by ownedbycats

To find books that have entries not present in the categories, I search for #fanficcat:true AND @Fanfiction.Fandoms:.false. Is it possible to also check this with a template?

I'm not familiar with using @ in a search like that and can't find it in the user manual. How does that work?

[ownedbycats]

You need to set up a user category. In the tag browser click 'configure' and then 'manage authors, tags > user categories.'

[isarl]

So it's effectively a prefix for user categories in the same way that # is a prefix for user columns?