NAME¶
RefDB::Makestyle - methods used by refdb-ms (RefDB style generator)
SUMMARY¶
Makestyle.pm - a module used by
refdb-ms (RefDB MakeStyle) -- a utility
that generates RefDB bibliography
styles.
Provides "Element" and "Attribute" classes for use in
generating RefDB
styles.
DEPENDENCIES¶
The following perl modules are required by this library:
- •
- Scalar::Util
Provides a method of querying an object to determine its base class.
- •
- Term::Clui
Provides user interface.
For input it provides mechanisms for selection from menus, direct input and
for yes/no question-answer prompts.
For output it provides for console output or display in the default editor.
This module, by default, records user choices in a hidden database. This
behaviour is turned off.
Term::Clui::edit uses a console editor for display. It uses the editor
specified by the EDITOR variable. If this variable is not set it falls
back to the 'vi' editor.
- •
- Text::Wrap
Provides word-wrap for console display.
- •
- File::Temp
Provides useful methods for filename generation.
The OO methods are not used because, at the time of writing, the version
shipped with some *nix-like OSes does not yet include the OO
interface.
UNIVERSAL METHODS¶
These methods are supplied by a hidden base class.
- •
- get_classname
Returns classname of object.
- •
- _is_valid_value
Default method for determining validity of simple (scalar) user input.
Checks that value is defined and not an empty string and not filled with
whitespace.
Is overridden by derived classes with more stringent input
requirements.
- •
- _input_choice
User selects from a menu.
Returns user's selection.
Parameters: (0 = class), 1 = prompt, 2... = options.
Common usage:
my $value = undef;
while ( 1 ) {
$value = $self->_input_choice( "Select value:" , <@list> );
if ( $value ) { last; }
print "Invalid choice. Sorry, please try again.\n";
}
- •
- _input_ask
User enters a value.
Returns user's input.
Parameters: (0 = class), 1 = prompt, 2 = default.
Common usage:
my $value = undef;
while ( 1 ) {
$value = $self->_input_ask( "Enter value:" , <$default> );
if ( $self->_is_valid_value( $value ) ) { last; }
}
- •
- _input_confirm
User is asked a question to which s/he answers y/n.
Returns boolean.
Parameters: (0 = class), 1 = question.
Note: If multi-line question, then after answer only the first line is left
on screen. The first line should be a short question with subsequent lines
holding further information.
Common usage:
if (_input_confirm( "Short question?\n\nMore\nmulti-line\ntext." ) ) {
# do stuff
}
- •
- _display
Displays screen text with word wrapping.
Parameters: (0 = class), 1 = display string.
Common usage:
_display( <$scalar> );
- •
- _view
Displays large volume of text in default editor and then returns viewer to
original screen.
Parameters: (0 = class), 1 = title , 2 = help text.
Common usage:
_view( <$title> , <$help_text> );
- •
- _entitize
Takes string and replaces '&', '<' and '>' with xml entity
equivalents.
ATTRIBUTE CLASSES¶
These classes model the XML attributes found in the Refdb "citestylex"
DTD.
Attributes: Public Interface¶
Attributes: Data Members
%self = (
name => "ATTRIBUTE" ,
enumeration => [ "value_0" , "value_1" , ... ] ,
default => "value_x" ,
prompt => "This is the purpose and/or use of the attribute." ,
value => "User selected/entered value>" ,
summary => 0 | 1 ,
)
- •
- name
Attribute name as per the Refdb "citestylex" DTD. Always
uppercase.
- •
- enumeration
List of possible values for attribute. If empty then attribute takes
user-entered value, eg. DISPLAYAUTHOR, which takes a number.
- •
- default
The default value. If "enumeration" is present, the default will
always be one of the items in it. If no default then leave as
"undef" -- this is the 'default' value after object
construction.
- •
- prompt
The text string that is used by client methods to prompt users when entering
data.
- •
- summary
Boolean determining whether attribute is included in summary form.
- •
- value
The attribute value as selected or input by the user.
Attributes: Constructors
In following method signatures replace ATTRIBUTE with the relevant attribute
class name.
Some attributes have a maximum number of instances that can exist within a given
PubType (see method
select_value below). When a class is asked to
create an object in excess of the designed maximum for that class the
constructor returns a scalar holding an error message. This enables a simple
test (using "ref" function) to determine whether the constructor
returned an object/blessed variable or scalar.
my $at = ATTRIBUTE->new();
Attributes: Setters
$at->set_name ( "<name>" );
$at->set_default ( "<default>" );
$at->set_prompt ( "<prompt>" );
$at->add_enumeration ( LIST );
$at->set_summary ( 0 | 1 );
Attributes: Getters
$at->get_name();
$at->get_default();
$at->get_prompt();
$at->get_enumeration(); # returns list with default value first
$at->get_enum_string(); # returns single text string
$at->get_summary();
$at->get_value();
Attributes: Other methods
- •
- $at->select_value();
If enumeration exists then user selects from list. The default is always the
first option in the list.
If there is no enumeration the user enters the value directly. The default
value is given and can be selected by simply pressing "Enter".
Some attributes are set automatically depending on how many objects of this
class have been created. In those classes this method has no effect. This
applies to the Role_AuthorList, Role_PubDate,
Role_Title, Role_UserDef, Role_Link and
Role_Misc classes.
The "citestylex" DTD design envisages a maximum number of objects
of these classes being constructed -- the number varying between 3 and 5
depending on the class. See "Attributes: Constructors" for what
happens when the class is asked to create an object in excess of the
designed maximum.
- •
- $at->get_xml_fragment();
Returns minimal xml fragment indicating the attribute name and value:
ATTRIBUTE="VALUE"
Attributes: List of Classes¶
To see a list of attribute classes use the "document-dtd-entities"
utility that shipped with this program. It extracts attribute and element
properties from this script, assembles and formats them into a single html
document.
ELEMENT CLASSES¶
These classes model the XML elements found in the Refdb "citestylex"
DTD.
Elements: Public Interface¶
Elements: Data members
%self = (
name => "ELEMENT" ,
prompt => "This is the purpose of this element." ,
help => "This is help on how to use this element." ,
display => undef | "name" | "content" ,
summary => undef | "name" | "left" | "right" | "content" ,
attributes => {
mandatory => [ "Attribute_Class_0" , "Attribute_Class_1" , ... ] ,
optional => [ "Attribute_Class_0" , "Attribute_Class_1" , ... ] ,
selected => [ "Attribute_0" , "Attribute_1" , ... ] ,
man_complete => undef | 1 ,
opt_complete => undef | 1 ,
} ,
copyable => 1 | undef ,
content => {
allowed => undef | 1 ,
suggestion => "Possible value" ,
value => "User input" ,
complete => undef | 1 ,
} ,
model_order => [
[ Element_Class_0 , "? | + | 1" ] ,
[ Element_Class_1 , "? | + | 1" ] ,
... ,
] ,
model_noorder => {
element_list => [ Element_Class_0 , Element_Class_1 , ... ] ,
separator => "Separator" ,
} ,
children => {
elements => [ Element_0 , Element_1 , ... ] ,
complete => boolean ,
)
- •
- name
Element name as given in the Refdb "citestylex" DTD. Unique.
- •
- prompt
Brief statement of the element's purpose and/or function.
- •
- help
More detailed instructions on how to use this element.
- •
- display
Determines whether, and how, to display the element in brief form (used for
the "progress report". If defined, the element is displayed. If
set to "name" the element name is displayed. If set to
"content" the element contents are displayed.
- •
- summary
Determines whether, and how, to display the element in summary form. If
defined, the element is displayed. If set to "name" the element
name is displayed. If set to "content" the element contents are
displayed.
- •
- attributes
Attributes of this element. First two lists are of 'legal' attributes:
mandatory and optional. Third list is of added attribute objects --
initially empty. Fourth and fifth hash values are flags indicating whether
attributes have been added.
- •
- content
Some elements hold #PCDATA content. The hash key "allowed"
determines whether element accepts input -- false/undef
means it does not, true means it does. The hash key
"suggested" holds a suggested value the user may use. The hash
key "value" holds the actual user input. The hash key
"complete" is a flag indicating whether content has been
entered.
- •
- copyable
Some elements cannot be copied, either because they have mandatory
attributes which require user input or because they only occur once per
citstyle.
- •
- model_order
With model_noorder this data member determines the content model for
children elements. All of the 64 elements fall into one of three content
models regarding children elements: 1. No children elements, 2. An ordered
list and 3. An unordered list.
This data member is "undef" in cases (1) and (3).
It holds the content model for the thirty elements which have content model
(2) -- an ordered list:
( e[?|+|1] , e[?|+|1] , ... )
where 'e' is the element and the symbols indicate 0-1, 1 or more, and
exactly 1 occurrence, respectively.
This data member holds an array of arrays. Each secondary array has two
items: the element class and the number of objects that can be
children.
- •
- model_noorder
With model_order this data member determines the content model for
children elements. All of the 64 elements fall into one of three content
models regarding children elements: 1. No children elements, 2. An ordered
list and 3. An unordered list.
This data member is "undef" in cases (1) and (2).
It holds the content model for the four elements (AUTHORONLY, INTEXTDEF,
PUBTYPE and YEARONLY) which have content model (3) -- an unordered list:
( ( e | e | ... ) , e? )+
where 'e' is an element, '?' is 0 or 1 occurrence and '+' is 1 or more
occurrances.
This data member holds a hash where the first key points to an array holding
the list of alterate elements in the content model inner brackets. The
second key points to the element represented in the content model as 'e+'
(in every case it is SEPARATOR).
- •
- children
This data member holds a hash. The first hash key ("elements")
points to an array holding the children elements added by the user. The
second hash key ("complete") is a boolean indicating whether all
children have been added.
Elements: Constructors
In following method signatures replace ELEMENT with the relevant element class
name.
my $el = ELEMENT->new();
Elements: Setters
$el->set_name( "<name>" );
$el->set_prompt( "<prompt>" );
$el->set_help( "<help>" );
$el->set_display( undef | "name" | "content" );
$el->set_summary( undef | "name" | "left" | "right" | "content" );
$el->set_attributes( %hash );
$el->set_mandatory_attributes_complete( "1" | undef );
$el->set_optional_attributes_complete( "1" | undef );
$el->set_content( %hash );
$el->set_content_complete( "1" | undef );
$el->set_order( @ArrayOfArrays );
$el->set_noorder( %hash );
$el->set_complete( "1" | "0" | undef );
$el->_set_value( "<value>" );
Elements: Getters
$el->get_name();
$el->get_prompt();
$el->get_help();
$el->get_display();
$el->get_summary();
$el->get_attr_mandatory(); # list: $self->{attributes}->{mandatory}
$el->get_attr_optional(); # list: $self->{attributes}->{optional}
$el->get_attr_selected(); # list: $self->{attributes}->{selected}
$el->get_suggestion(); # scalar: $self->{content}->{suggestion}
$el->get_value(); # scalar: $self->{content}->{value}
$el->get_order(); # AoA: $self->{model_order}
$el->get_noorder_list(); # list: $self->{model_noorder}->{element_list}
$el->get_noorder_separator; # scalar: $self->{model_noorder}->{separator}
$el->get_children(); # list: $self->{children}->{element}
$el->get_last_child(); # object: $self->{children}->{element}[<last>]
Elements: Other methods
- •
- $el->content_is_complete();
Returns boolean indicating whether element content has been entered.
Indicated by a data member which is set after "enter_value()"
method called.
- •
- $el->enter_value();
User enters element value if element can legally hold one. User may be
presented with a suggested value.
If the element cannot accept a value nothing happens -- no error
message/value is generated.
- •
- $el->is_content_allowed();
Returns boolean indicating whether the element can hold content.
- •
- $el->children_are_complete();
Returns boolean indicating whether all children have been added.
Simply returns $self->{children}->{complete} and relies on other
subroutines having set it appropriately.
- •
- $el->max_attribute_index();
Returns maximum index value of selected attributes list: -1 if empty
list.
- •
- $el->max_child_index();
Returns maximum index value of element children list: -1 if empty list.
- •
- $el->is_last_element();
Determines whether element index is the last element in the list of children
in the ordered child model: $self->{model_order}.
Parameters: [ 0 = class ] , 1 = array index.
- •
- $el->is_last_child();
Determines whether child index is the last element in the list of children:
$self->{children}->{elements}.
Parameters: [ 0 = class ] , 1 = array index.
- •
- $el->is_creatable();
Returns a boolean indicating whether this element class can legally create
another object.
Intended to be called as a class method.
- •
- $el->list_selectable_attributes();
Returns a list of all optional attributes available for selection. List
consists of all attributes listed in 'optional' list minus all
attributes already selected.
- •
- $el->_build_attribute_help();
Helper method for method "add_attributes_optional". Takes as
parameter a list of attributes for which help screen is being built.
Includes "name" and "prompt" for each attribute.
- •
- $el->has_mandatory_attributes();
Returns boolean indicating whether element has mandatory attributes.
- •
- $el->_is_closed_tag();
Returns boolean indicating whether element can be represented by closed tag.
Requires no possible child elements and no current content.
- •
- $el->get_xml_brief_tag();
Returns opening xml tag for element.
Shows only mandatory attributes.
- •
- $el->get_xml_open_tag();
Returns opening xml tag for element.
Parameters: [ 0 = class ] , 1 = show attributes (bool) , 2 = show content
(bool).
Designed to be used in conjunction with "get_xml_close_tag"
method. If element has no potential child elements and no content, then
will return closed tag, eg. <ELEMENT/>.
- •
- $el->get_xml_close_tag();
Returns closing xml tag for element.
Designed to be used in conjunction with "get_xml_open_tag" method.
If element has no potential child elements and no content, then will
return no closing tag since "get_xml_open_tag" will have
returned a closed tag, eg. <ELEMENT/>.
- •
- $el->generate_full_xml();
Generates full xml for element.
Displays all attributes and element content. If no possible child elements
and no current element content, will display closed tag, eg.
<ELEMENT/>.
Method is recursive.
Parameters (receives): [ 0 = class ] , 1 = element count , 2 = indent/tab
count and 3 = output.
Returns: 0 = element count and 1 = output.
- •
- $el->get_a_child();
Returns a single child element matching supplied array index. Returns
"undef" if index out of bounds.
Parameter: [ 0 = class ] , 1 = index.
- •
- $el->show_progress();
Generates abbreviated xml for element and element children. Designed to show
user's "progress" to date.
Displays only opening tags. Child elements are displayed only where element
is not set to "complete".
Only mandatory attributes are displayed.
Method is recursive.
Parameters (receives): [ 0 = class ] , 1 = output , 2 = stop flag.
Returns: 0 = output.
Algorithm (recursive):
if self is a stop element
set stop flag = true
endif
add self to output
if stop flag == true and children are complete
return 'output'
else
repeat for all children
recurse (returns 'output')
endrepeat
return 'output'
endif
if matching element
set stop flag = true
endif
add to output
if stop flag true
if is complete
if has children
recurse
else
add fragment to output
endif
else # not complete
if has children
repeat for all children
recurse (returns 'retval')
set output = 'retval'
endrepeat
endif
return output
- •
- $el->generate_brief_xml();
Generates abbreviated xml for element. Designed to show user's
"progress" to date.
Displays only opening tags. Child elements are displayed only where element
is not set to "complete".
Only mandatory attributes are displayed.
Method is recursive.
Parameters (receives): [ 0 = class ] and 1 = output.
Returns: 0 = output.
- •
- $el->get_full_tag();
Returns opening +/- closing xml tag for element.
Displays all attributes and element content. If no possible child elements
and no current content, will display single closed tag, eg.
<ELEMENT/>.
- •
- $el->_test_attributes_mandatory();
Intended as helper method for "is_creatable". Tests that mandatory
attributes can be created.
Note: The attributes are not actually added to the element.
Returns boolean. False value indicates failure adding mandatory attributes
and the associated element should be detroyed.
- •
- $el->add_attributes_mandatory();
Mandatory attributes are immediately added (note: mandatory attributes
should have been added during element construction).
Returns boolean. False value indicates failure adding mandatory attributes
and the associated element should be detroyed.
Can be run in 'silent' mode with no output from method. There are no
guarantees about the 'silence' of attributes' "select_value"
method, but all such methods should not generate output.
Parameters: [ 0 = class ] , [ 1 = <text> | 1 ]
- •
- $el->add_attributes_optional();
The user selects optional attributes to add. Help is available. Element
feedback is presented as the user proceeds.
- •
- $el->mandatory_attributes_complete();
Returns boolean indicating whether mandatory attributes have been added.
Indicated by a data member which is set after "add_attributes()"
method called.
- •
- $el->optional_attributes_complete();
Returns boolean indicating whether optional attributes have been added.
Indicated by a data member which is set after "add_attributes()"
method called.
- •
- $el->add_attributes();
First adds the mandatory attributes and then gives user chance to add
optional attributes.
Returns boolean indicating whether attributes added successfully. Only
mechanism of failure occurs when element requires mandatory attribute such
as ROLE which cannot be added because maximum number of ROLE attributes
already exist for this PUBTYPE.
- •
- $el->add_child();
Adds a child to the current element.
Parameters: [ 0 = class ] , 1 = child element (object).
- •
- $el->_select_next_child_order();
Helper method for method "select_next_child". Used when element
has a modal content model. Help is provided where appropriate.
Returns two element list: 0 = message indicating whether selection was
forced by the content model or chosen by user , 1 = element class name.
Note: If user makes no selection, and content model forces none, an
"undef" element class name is returned along with an informative
message.
When content model is exhausted the content flag --
$self->{children}->{complete} -- is set to true.
The algorithm for this subroutine is the nastiest in the program. I include
it here in full for future occasions when I may have to debug.
if no current child elements
set OUT_OF_CHILDREN = true
else
set OUT_OF_CHILDREN = false
endif
begin loop
if OUT_OF_CHILDREN == true
switch require
case +
if PREV != element
EXIT: mandatory element
else # ( PREV_CHILD == element )
ASK: repeat element
if yes
EXIT: chosen element
else # ( no )
if last element
set children_full flag = true
EXIT: END
else # ( not last element )
advance element
endif
endif
endif
endcase
case 1
if last element
set children_full flag = true
endif
EXIT: mandatory element
endcase
case ?
ASK: add element
if yes
EXIT: chosen element
else # ( no repeat )
if last element
set children_full flag = true
EXIT: END
else # ( not last element )
advance element
endif
endif
endcase
endswitch
else # ( OUT_OF_CHILDREN == false )
if child == element
switch require
case ? | 1
if last child
if last element
set children_full flag = true
EXIT: END
else # ( not last element )
advance element
set OUT_OF_CHILDREN = true
endif
else # ( not last child )
if last element
ERROR: exhausted content model but got $child
else # ( not last element )
advance element
set PREV_CHILD = null
advance child
endif
endif
endcase
case +
if last child
ASK: repeat element
if yes
EXIT: optional element
else # ( no repeat )
if last element
set children_full flag = true
EXIT: END
else # ( not last element )
advance element
set OUT_OF_CHILDREN = true
endif
endif
else # ( not last child )
set PREV_CHILD = child
advance child
endif
endcase
endswitch
else # ( child != element )
switch require
case +
if last element
ERROR: expecting $element, got $child
else # ( not last element )
if PREV_CHILD == element
set PREV_CHILD = null
advance element
else # ( PREV_CHILD != element )
ERROR: expecting $element, got $child
endif
endif
endcase
case ?
if last element
ERROR: content model exhausted, no match for $child
else # ( not last element )
advance element
endif
endcase
case 1
ERROR: expecting $element, got $child
endcase
endswitch
endif
endif
end loop
Warning: In a number of places in this subroutine the program can
"die". This occurs when a mismatch between the child element
model and the actual child elements is detected. If the mismatch truly
exists it is a coding error since the algorithm should force child
elements to match the content model. If the mismatch is not real the code
has erred in analysing the data. Either way, it is an unrecoverable error
and the algorithm/code must be corrected.
- •
- $el->list_selectable_children_noorder();
Used when selecting child elements when following the unordered model.
Returns a list of all optional elements available for selection. List
consists of all elements attributes listed in 'optional' list minus
all attributes already selected.
- •
- $el->_build_element_help();
Helper method for method "_select_next_child_noorder". Takes as
parameter a list of elements for which help screen is being built.
- •
- $el->_select_next_child_noorder();
The user selects optional child element to add.
Helper method for 'select_next_child'.
Returns two element list: 0 = message indicating whether selection was
forced by the content model or chosen by user , 1 = element class name.
Note: If user chooses to finish child element selection, "undef"
element class name is returned along with an informative message.
When child element selection is finished the content flag --
$self->{children}->{complete} -- is set to true.
Help is available.
No option to exit until at least one element has been selected.
Cannot select two "Separator" elements consecutively.
- •
- $el->select_next_child();
The user selects a child element to add. Help is available.
Returns two element list: 0 = text indicating whether mandatory or user
choice ,
1 = element class name.
Note: If user makes no selection, and content model forces none, an
"undef" element class name is returned along with an informative
message.
The algorithm for this subroutine is the nastiest in the program. I include
it here in full for future occasions when I may have to debug.
- •
- $el->is_copyable();
Returns boolean indicating whether element can be copied.
Based on value of $self->{copyable}.
- •
- $el->copy();
Attempts to copy element. Returns either a reference to a copied element or
an error message.
Can test for success using "ref" function.
Does not copy attributes. Attributes requiring user input during creation
are not copyable (this includes Type_PubType, Role_UserDef, Role_Misc and
Role_Link).
Does not copy child elements. For that, use the "duplicate"
method.
- •
- $el->has_attributes();
Returns boolean indicating whether element has attributes.
- •
- $el->has_children();
Returns boolean indicating whether element has children.
- •
- $el->_push_attribute();
Adds attribute to element.
Parameters: [ 0 = class ] , 1 = attribute object.
- •
- $el->duplicate();
Returns either a reference to a duplicate element or an error message.
Copies all attributes, child elements and element content.
- •
- $el->duplicate();
Returns either a reference to a duplicate element or an error message.
Copies all attributes, child elements and element content.
- •
- $el->is_ordered_child_model();
Returns boolean indicating nature of child element content model.
- •
- $el->is_unordered_child_model();
Returns boolean indicating nature of child element content model.
- •
- $el->is_childless_model();
Returns boolean indicating nature of child element content model.
- •
- $el->get_last_parent();
Return reference to last parent element.
Parameters: [ 0 = class ] , 1 = originator flag (true if not originating
element)
Recursive algorithm:
if child elements
recurse last child (returns 'retval')
if 'retval' is element
return 'retval'
else
return self
endif
else
if recursed element
return undef
else
return self
endif
endif
- •
- $el->get_last_element();
Return reference to last element.
Recursive algorithm:
if child elements
recurse last child (returns 'retval')
return 'retval'
else
return self
endif
- •
- $el->delete_last_child();
Delete last child of this element.
Returns element.
- •
- $el->delete_last_element();
Delete last element.
Return deleted element.
- •
- $el->has_incomplete_descendent();
Returns boolean indicating whether any descendent of element is
incomplete.
- •
- $el->get_last_incomplete();
Return reference to last element in tree that is incomplete.
Returns "undef" if all elements complete.
Recursive algorithm:
if child elements
recurse last child (returns 'retval')
if 'retval' is element
return 'retval'
endif
else
if not complete
return self
else
return undef
endif
endif
- •
- $el->is_named();
Returns boolean indicating whether element has display data member set to
"name".
- •
- $el->get_last_named();
Return reference to last element in tree with display data member set to
'name'.
- •
- $el->get_style_name();
Finds StyleName element and returns element content.
If unsuccessful, return "undef".
- •
- $el->get_most_recent();
Return reference to last element in tree of supplied element class.
If no element found, return "undef".
- •
- $el->reset_all_counters();
Resets all role level counters
Called by PubType, AuthorOnly, YearOnly and InTextDef during element
creation.
- •
- $el->named_in_summary();
Boolean indicating whether to include element in summary.
- •
- $el->content_in_summary();
Boolean indicating whether to include raw element content in summary.
Currently only applies to SEPARATOR.
- •
- $el->has_bracketing_child();
Boolean indicating whether element has any child elements whose content will
"bracket" this element's content in output. Currently only
applies to PRECEEDING and FOLLOWING.
- •
- $el->generate_summary();
Generates substantial portion of style summary. Called by UI method
'write_summary'.
Parameters: [ 0 = class ] , 1 = previous output.
Returns: 0 = current output.
Since this method is only called on a complete style, we can make
assumptions based on the style following the DTD.
Recursive algorithm.
switch <element class>
case 'StyleName'
add to output: style name
endcase
case 'RefStyle'
add to output: header = "Bibliography Style"
endcase
case 'PubStyle'
add to output: header giving publication type
endcase
case 'CitStyle'
add to output: header = "Citation Style"
endcase
case 'InTextDef'
add to output: header = Author and Year
endcase
case 'AuthorOnly'
add to output: header = Author
endcase
case 'YearOnly'
add to output: header = Year
endcase
endswitch
if summary flag == name
if bracketing child element(s)
set bracket flag = true
endif
if bracket flag == true
add to output: opening brackets
endif
if bracket flag == true
if left bracketing element present
print left bracketing element contents
endif
endif
add to output: left marker
add to output: element name
repeat for all attributes
if attribute summary flag == true
add to output: attribute value (italicised)
endif
endrepeat
add to output: right marker
endif
if have children
repeat for all children
** recurse (send output, receive output as 'retval')
endrepeat
endif
return output
Elements: List of Classes¶
To see a list of attribute classes use the "document-dtd-entities"
utility that shipped with this program. It extracts attribute and element
properties from this script, assembles and formats them into a single html
document.
All elements descend from one of three ancestor classes depending on their
content model:
- •
- _Model_Childless
Elements descended from this class have a content model specifying no
children elements.
- •
- _Model_Order
Elements descended from this class have a content model of the general form:
( element_A[?|+] , element_B[?|+] , ... )
- •
- _Model_Noorder
Elements descended from this class have a content model of the general form:
( element_A | element_B , ... ) , element_X? )+
USER-INTERFACE CLASS¶
This class holds the user-built bibliography style.
UI: Public Interface¶
UI: Data members
%self = (
help => {
<help topic> => <help text> ,
...
} ,
cache => {
"element_class_A" => element_A ,
"element_class_B" => element_B ,
...
} ,
root => "undef" | element ,
filename => undef | <filename>,
)
- •
- help
Introductory help system.
Is a hash consisting of <"help topic" : "help
text"> pairs.
- •
- cache
Cache for frequently used elements.
First hash key ("cachable") points to list of cachable elements.
Second has key points to subsidiary hash which holds key:value pairs of
element class names and the corresponding element.
- •
- root
Location of style's root element.
- •
- style_file
Name of style file. Set after successful output.
- •
- summary_file
Name of summary file. Set after successful output.
UI: Constructors
my $ui = UI->new();
UI: Setters
$ui->set_root( <element> );
$ui->set_style_file( "<filename>" );
$ui->set_summary_file( "<filename>" );
UI: Getters
$ui->get_help_topics(); # list: keys ( $self->{help} )
$ui->get_help( "<topic>" ); # scalar: value ( $self->{help}->{<topic>} )
# takes parameter: help topic
$ui->get_cachable(); # list: $self->{cache}->{cachable}
$ui->get_cached(); # list: defined( $self->{cache}->{elements} )
$ui->get_cached_element( "<class>" );
# object: cached element
$ui->get_root(); # object: root element
$ui->get_style_file(); # scalar: style file filename
$ui->get_summary_file(); # scalar: summary file filename
UI: Other methods
- •
- $ui->help_system();
Runs help system -- a menu allowing the selection of a series of
- •
- $ui->get_last_parent();
Returns reference to last parent element.
- •
- $ui->can_copy_recent();
Returns booelan indicating whether element can copy recent version of
itself.
Parameters: [ 0 = class ] , 1 = element class | object
- •
- $el->delete_selected_element();
Gives the user the option of deleting element(s).
Depending on the state of the element tree, the user can delete the last
element or the last major ("named") element. A "named"
element has its 'display' data member set to 'name' -- in general they are
the elements corresponding to ris fields.
A "complete" element has had all children added and its
'children->complete' data member is set to true ("1").
Algorithm is:
get last named element
if element is complete
repeat until last named element is deleted
delete last element
endrepeat
else
delete last element only
endif
- •
- $ui->create_element();
Creates element. If element of class already exists, user can duplicate most
recent.
- •
- $ui->startup_checks();
Currently checks for: write access to current directory.
- •
- $ui->get_output_filename();
Returns filename for output file. Uses File::Temp module.
If filename does not exist in current directory, simply return default.
If it does, then user must select new filename. File::Temp is used to
provide a suggestion based on the default filename.
Requires the following parameters: [ 0 = class ] , 1 = default filename , 2
= filename template pattern , 3 = filename template suffix , 4 = prompt.
Parameters 2 and 3 are in the format required by File::Temp. Parameter 2
must end in at leat 4 'X's -- these will be replaced with random digits.
The suffix is the part of the filename following the part specified by
parameter 2. It is not restricted to a DOS-style three letter extension.
Example: Default filename (parameter 1) = 'experimental-style.xml'. Filename
template pattern (parameter 2) = 'experimental-XXXX'. Filename template
suffix (parameter 3) = '-style.xml'. Prompt (parameter 4) = 'Enter name
for style file:'.
- •
- $ui->write_style();
Writes style to file. Checks filename doesn't already exist. If so, proposes
alternative.
- •
- $ui->write_summary();
Writes style summary to file. Checks filename doesn't already exist. If so,
proposes alternative.
- •
- $ui->get_command_base();
Gets base for refdba commands. Involves checking for access to refdba. Also
determines whether username and password required.
If succeeds, returns base command of the form:
refdba [-u <username> -w <password>] -C
If fails, returns "undef".
- •
- $ui->upload_style();
Uploads style to refdb. If style of same name already exists, attempt to
save it to disk.
AUTHOR¶
David Nebauer, david <at> nebauer <dot> org
COPYRIGHT AND LICENSE¶
Copyright (C) 2004 by David Nebauer
This library is distributed under the same license and conditions as the
"RefDB" project <<
http://refdb.sourceforge.net/>>.
