EPScript/Functions

Functions

Calling Functions

Functions can be called in two ways:

 <when test="is_set( creators )">

or

 <when test="creators.is_set">

These are interchangable, but it may be beneficial to use a specific form in some cases.

Generic Functions

is_set

Returns true if the parameter is set, based on the following criteria:

• If the parameter is a string, it is set if it is not empty.
• If the parameter is a list or a complex structure, it is set if at least one value is set.

 <when test="is_set( creators )">
   ...
 </when>

yesno

Returns a yes or no string depending on whether the expression is true.

 <print expr="yesno(is_set('abstract'))" />

List Functions

length

Returns the number of items in the list.

 <if test="length(editors) gt 1">s</if>

one_of

Returns a boolean depenbding on whether a variable is one of a number of values.

 <when test="type.one_of('article','conference_item','book')">
   ...
 </when>

String Functions

reverse

Returns the reverse of a string (i.e. 'abc' becomes 'cba').

 <when test="type.reverse = 'tnetap'">
   ...
 </when>

join

Returns the concatentation of strings with a particular joining character.

 <when test="$list.join(':') = 'a:b:c'">
   ...
 </when>

substr

Returns the substring of a string

 <when test="title.substr(0,3) = 'the'">
   ...
 </when>

contains

Returns a boolean depending whether the string contains a particular substring.

 <when test="title.contains('the')">
   ...
 </when>

as_string

Converts variable into a string. Can be useful in phrases or for defining class or id attributes for HTML elements

 <phrase ref="licenses_description_{license.as_string()}" />.

strlen

Gets the integer length of a string.

 <when test="strlen(title) > 50">
   ...
 </when>

Mathematical Functions

add

Returns the addition of one number to another.

 <when test="pages + 4 > 10">
   ...
 </when>

subtract

Returns the substraction of one number from another.

 <when test="pages - 4 lt 10">
   ...
 </when>

multiply

Returns the multiplication of one number by another.

 <when test="pages * 4 gt 10">
   ...
 </when>

divide

Returns the division of one number by another.

 <when test="pages / 4 lt 10">
   ...
 </when>

mod

Returns the modulus (i.e. remainder) of a number from a base (e.g 5 % 3 equals 2.

 <when test="pages % 2 = 0">
   ...
 </when>

uminus

Returns the negative value of an integer (e.g. 1 becomes -1). This is a unary rather than binary operator like substract.

 <when test="-rating gt 5">
   ...
 </when>

Rendering Functions

citation

Renders the XHTML citation for a data object with a specified style. Encapsulated within a link to

 <print expr="$item.citation('default')" />

citation_link

Renders the XHTML citation for a data object with a specified style, where the title is encompassed by a link to the data object.

 <print expr="$item.citation_link('default')" />

embed_video

Renders an XHTML object to render an HTML5 video preview for a document that is a video or audio file.

 <print expr="$doc.embed_video" />

Data Object Functions

property

Get the property of a data object

 <print expr="$item.property('note')">

main_item_property

Get the property of parent data object.

 <print expr="$doc.main_item_property('note')" />

as_item

Treats a variable as an item so other data object functions can be applied to it.

  <when test="$doc.property('eprintid').as_item().property('type') = 'thesis'">

dataset

Returns the string for the dataset of the data object.

  <when test="$item.dataset() = 'document'">

related_objects

Returns an array of objects related to the current data object through a particular property.

 <foreach expr="$doc.related_objects('http://eprints.org/relation/hasVersion')" iterator="rel">

url

Returns the URL for a particular data object.

 <a href="{$doc.url()}">Download</a>

Date Functions

today

Returns today's date

 <print expr="today()" />

datemath

Returns a date relative to the date provided, (e.g. two years ago).

 <when test="date lt today().datemath( -2,'year' )">