RenderObjects templates

Introduction

The template language for RenderObjects can be described as follows. It is a list of the following kinds of string:

Basic emitting commands

{{ id_d }}: Emits the id_d of the object under consideration.
Only available in RenderObjects, not RenderXML.
{{ firstmonad }}: Emits the first monad of the object under consideration. This is done in base-10, so that if an object has a set of objects with first monad "3", then "3" is emitted (without the quotes).
Only available in RenderObjects, not RenderXML.
{{ lastmonad }}: Emits the last monad of the object under consideration. This is done in base-10, so that if an object has a set of objects with last monad "3", then "3" is emitted (without the quotes).
Only available in RenderObjects, not RenderXML.
{{ dbname }}: Emits the database name under consideration. This is the database name given to the constructor of the RenderObjects class.
Only available in RenderObjects, not RenderXML.
{{ feature integer }}: Emits the value of the object's feature given by the integer's 0-based index into the list of features in the "get" part of the stylesheet for this object type. Thus if the "get" part says '"get" : [ "surface", "suffix" ]', and the "start" part says: '"start" : "{{ feature 1 }}"', then the value of the object's "suffix" feature is emitted. The feature value is escaped (mangled) according to XML rules, such that less-than becomes "<", greater-than becomes ">", ampersand becomes "&", and "double tuote" becomes """.
Only available in RenderObjects, not RenderXML.
{{ featurenomangle integer }}: Just like the "feature" counterpart just described, except that no XML mangling takes place.
Only available in RenderObjects, not RenderXML.
{{ counter string }}: Emits the contents of the "counter" within the template execution environment, named by the given string. A counter is simply an integer which has a name, and which can be incremented and emitted. It always starts at 0, so the first time you use this, 0 will be emitted, unless you have used "inccounter", "deccounter" or "setcounter" first.
{{ counter string format format-string }}: Emits the contents of the "counter" within the template execution environment, named by the first string, formatted using the format-string.

The format-string is currently limited to the following cases. For example:
- Empty No formatting is done on the integer. It is just printed as a base-10 number.
- 017 I.e., a 0-prefixed integer (e.g., 17). This makes sure that the number string is at least as long as the given integer (e.g., 17 characters long), and padded with '0', ASCII 48=0x32.
- 17 I.e., a non-0-prefixed integer. Same as 017, except that the padding charater is a space: ASCII 32=0x20.

Document control commands

{{ setnixing doc }}: Starts "nixing" the output to the document, i.e., no strings are emitted at all to the output. Strings are emitted to variables and lists, however. But variables and lists are not emitted to the document. This state continues until you use "setnixing off" or "setnixing all".
{{ setnixing all }}: Starts "nixing" ALL output to the document and to lists and variables, i.e., no strings are emitted at all to the output, lists, or variables. This state continues until you use "setnixing off" or "setnixing doc".
{{ setnixing off }}: Stops "nixing" (see "setnixing doc" and "setnixing all" just above).

Counter manipulation commands

{{ inccounter string }}: Increments the "counter" within the template execution environment which is named by the given string, adding 1. If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be incremented to 1.
{{ inccounter string integer }}: Increments the "counter" within the template execution environment which is named by the given string, adding the integer given. If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be incremented to the integer given.
{{ inccounter string var string }}: Increments the "counter" within the template execution environment which is named by the given string, adding the integer value contained in the variable named by the string after "var". If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be incremented to the integer given in the variable.
{{ deccounter string }}: Decrements the "counter" within the template execution environment which is named by the given string, subtracting 1. If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be decremented to -1.
{{ deccounter string integer }}: Decrements the "counter" within the template execution environment which is named by the given string, subtracting the integer given. If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be decremented to the integer given.
{{ deccounter string var string }}: Decrements the "counter" within the template execution environment which is named by the given string, subtracting the integer value contained in the variable named by the string after "var". If the counter does not exist when this template is called, it will be created, and will start at 0. It will then be decremented to the integer given in the variable.
{{ setcounter string integer }}: Sets the "counter" within the template execution environment which is named by the given string, setting it to the integer given. If the counter does not exist when this template is called, it will be created, and will be set to the integer given.
{{ setcounter string var string }}: Sets the "counter" within the template execution environment which is named by the first string, setting it to the integer value obtained from base-10 decoding the variable named in the second string. If the counter does not exist when this template is called, it will be created, and will be set to the integer given.

Variable manipulation commands

{{ setvar variable-name-as-string new-value-as-string }}: Sets the string contents of a variable with the name given to the value given. If the variable does not exist, it is created.
{{ setvar variable-name-as-string }} variable contents... {{ setvarend }}: Sets the string contents of a variable with the name given. If the variable does not exist, it is created. The contents of the variable are set to whatever appears until setvarend is met. This may include other templates, but may not include listappendbegin ... listappendend, nor may it include setvar. The setvarend template need not be in the same template string as the setvar template, i.e., the first setvarend met during execution will end the current (and only) setvar.
{{ emitvar variable-name-as-string }}: Emits the contents of the variable with the name given. If the variable does not exist, it is initialized to be the empty string.

List manipulation commands

{{ listappendbegin string }} list contents... {{ listappendend }} : Appends the contents up to the listappendend template tag to the list named by string. The contents may contain other templates, including listappendbegin ... listappendend. If the list does not exist, it is created. The contents will not be emitted until a listemit template tag which uses the name of the list is met in the processing. The listappendend need not appear in the same string as the corresponding listappendbegin. The listappendend ends the most recently begun list, i.e., a stack of list names is at work.
{{ listemit string string }}: Emits the elements of the list named by the first string. The second string is placed in between each list item.
{{ listclear string }}: Clears the list named by string (i.e., makes it empty).

Dictionary manipulation commands

{{ dictlookup dictname-as-string feature feature-index-as-integer default-as-string }}: Can only be used with fetchinfo, not renderinfo, since the features are only available in the fetchinfo stage. Looks up the dictionary with the given name under the "dictionaries" key of the fetchinfo stylesheet at hand, and then looks up the key given by the feature of the current object with feature index as given, and the emits the value, if found, or the default given, if not found.

The feature value is mangled according to XML rules. See the feature template tag on this page for an explanation.

Example: {{ dictlookup 'booknames' feature 0 'Unknown book ID' }}
{{ dictlookup dictname-as-string featurenomangle feature-index-as-integer default-as-string }}: This behaves just like the dictlookup ... feature ... counterpart, but does not XML-mangle the feature value before looking the feature value up. This can also only be used with fetchinfo, not renderinfo.

Example: {{ dictlookup 'booknames' featurenomangle 0 'Unknown book ID' }}
{{ dictlookup dictname-as-string var variable-name-as-string default-as-string }}: This behaves just like the dictlookup ... feature ... counterpart, but uses the contents of the given variable as the key into the dictionary. Additionally, it can be used both in fetchinfo and in renderinfo.

The contens of the variable are XML-mangled before the lookup. See the feature template tag for an explanation of XML-mangling.

Example: {{ dictlookup 'booknames' var 'bookID' 'Unknown book id' }}
{{ dictlookup dictname-as-string varnomangle variable-name-as-string default-as-string }}: This behaves just like the dictlookup ... var ... counterpart, but does not mangle the variable contents before looking up in the dictionary.
Example: {{ dictlookup 'booknames' var 'bookID' 'Unknown book id' }}
{{ dictlookup dictname-as-string counter counter-name-as-string default-as-string }}: This first sees if the given counter exists. If it does not, it is initialized to 0. Then, its value is converted to string in base-10. Then, the dictionary lookup is performed as for var and feature, but with the counter-value as the lookup key.

Example: {{ dictlookup 'number2letter_dict' counter 'footnotenumber' 'Unknown number' }}

Named set manipulation commands

The template language supports "named sets" of strings. The following template actions manipulate these.

{{ namedsetaddbegin string string }} named set contents... {{ namedsetaddend }} : Adds the string(s) up to the namedsetaddend template tag to the set named by first string. If the named set does not exist, it is created before any string is added. The contents will not be emitted until a namedsetemit template tag which uses the name of the set is met in the processing.

The second string is a delimiter string which, if non-empty, is used to cut up the content string into substrings, which are then added one by one.
{{ namedsetremovebegin string string }} named set contents to remove... {{ namedsetremoveend }} : Removes the string(s) up to the namedsetremoveend template tag from the set named by first string. If the named set does not exist, nothing happends.

The second string is a delimiter string which, if non-empty, is used to cut up the content string into substrings, which are then removed one by one.
{{ namedsetemit string string }}: Emits the elements of the set named by the first string, in memcmp lexicographic order. The second string is placed in between each set item, and may be empty.
{{ namedsetclear string }}: Clears the set named by string (i.e., makes it empty).

if-then-else flow control

{{ if featureequal integer "string-in-quotes" }}if-true-template{{ endif }}: Checks whether the string representation of the feature given by the 0-based index integer into the "get" list of features is equal to the "string-in-quotes". If it is, then the template if-true-template is executed. Otherwise, nothing is emitted.

This also has a different variant:
{{ if featureequal integer "string-in-quotes" }}if-true-template{{ else }}if-false-template{{ endif }}: Checks whether the string representation of the feature given by the 0-based index integer into the "get" list of features is equal to the "string-in-quotes". If it is, then the template if-true-template is executed. Otherwise, the if-false-template is executed.
{{ if varequal varname-as-string 'string-in-quotes' }}if-true-template{{ endif }}: Checks whether the variable given is equal to the "string-in-quotes". If it is, then the template if-true-template is executed. Otherwise, nothing is emitted.
{{ if varequal varname-as-string 'string-in-quotes' }}if-true-template{{ else }}if-false-template{{ endif }}: Checks whether the variable given is equal to the "string-in-quotes". If it is, then the template if-true-template is executed. Otherwise, the if-false-template is executed.
{{ if varequal varname-1-as-string var varname-2-as-string }}if-true-template{{ endif }}: Checks whether the variable varname-1-as-string equal to the variable varname-2-as-string. If it is, then the template if-true-template is executed. Otherwise, nothing is emitted.
{{ if varequal varname-1-as-string var varname-2-as-string }}if-true-template{{ endif }}: Checks whether the variable varname-1-as-string equal to the variable varname-2-as-string. If it is, then the template if-true-template is executed. Otherwise, the if-false-template is executed.
{{ if listempty listname-as-string }}if-true-template{{ endif }}: Checks whether the list by the name given is empty, or does not exist. If either of these is true, then the template if-true-template is executed. Otherwise, nothing is emitted.
{{ if namedsetempty named-set-name-as-string }}if-true-template{{ endif }}: Checks whether the set named by the given name is empty, or does not exist. If either of these is true, then the template if-true-template is executed. Otherwise, nothing is emitted.
{{ if listempty listname-as-string }}if-true-template{{ else }}if-false-template{{ endif }}: Checks whether the list by the given name is empty, or does not exist. If either of these conditions hold, then the template if-true-template is executed. Otherwise, the if-false-template is executed.

Note about XML mangling

All other strings: Are emitted verbatim, except that they are escaped for the XML entities '&', '<', '>', and '"', which map as follows:
- & --> &
- < --> <
- > --> >
- " --> "