Creator-defined statements allow you to add your own statements to Ren'Py. This makes it possible to add things that are not supported by the current syntax of Ren'Py.
Creator-defined statements must be defined in a python early
block. What's more,
the filename containing the user-defined statement must be be loaded earlier
than any file that uses it. Since Ren'Py loads files in Unicode sort order, it
generally makes sense to prefix the name of any file containing a user-defined
statement with 01, or some other small number.
A user-defined statement cannot be used in the file in which it is defined.
Creator-defined statement are registered using the renpy.register_statement()
function.
renpy.
register_statement
(name, parse=None, lint=None, execute=None, predict=None, next=None, scry=None, block=False, init=False, translatable=False, execute_init=None, init_priority=0, label=None, warp=None, translation_strings=None) linkThis registers a user-defined statement.
This is a function that is called to determine the next statement.
If block is not "script", this is passed a single argument, the object returned from the parse function. If block is "script", an additional argument is passed, an object that names the first statement in the block.
The function should return either a string giving a label to jump to, the second argument to transfer control into the block, or None to continue to the statement after this one.
The parse method takes a Lexer object:
Lexer
linkeol
() linkTrue if the lexer is at the end of the line.
match
(re) linkMatches an arbitrary regexp string.
All of the statements in the lexer that match things are implemented in terms of this function. They first skip whitespace, then attempt to match against the line. If the match succeeds, the matched text is returned. Otherwise, None is returned.
keyword
(s) linkMatches s as a keyword.
name
() linkMatches a name. This does not match built-in keywords.
word
() linkMatches any word, including keywords. Returns the text of the matched word.
image_name_component():
Matches an image name component. Unlike a a word, and image name component can begin with a number.
string
() linkMatches a Ren'Py string.
integer
() linkMatches an integer, returns a string containing the integer.
float
() linkMatches a floating point number, returns a string containing the floating point number.
label_name
(declare=False) linkMatches a label name, either absolute or relative. If declare is true, then the global label name is set. (Note that this does not actually declare the label - the statement is required to do that by returning it from the label function.)
simple_expression
() linkMatches a simple Python expression, returns it as a string.
delimited_python
(delim) linkMatches a pythio expression that ends in a delimiter, often ':' or '='.
arguments
() linkReturns an object representing the arguments to a function
call. This object has an evaluate
method on it that
takes an optional scope dictionary, and returns a tuple
in which the first component is a tuple of positional arguments,
and the second component is a dictionary of keyword arguments.
rest
() linkSkips whitespace, then returns the rest of the line.
checkpoint
() linkReturns an opaque object representing the current state of the lexer.
revert
(o) linkWhen o is the object returned from checkpoint(), reverts the state of the lexer to what it was when checkpoint() was called. (This is used for backtracking.)
subblock_lexer
() linkReturn a Lexer for the block associated with the current line.
advance
() linkIn a subblock lexer, advances to the next line. This must be called before the first line, so the first line can be parsed.
These functions are useful in writing lint functions.
Checks the text tags in s for correctness. Returns an error string if there is an error, or None if there is no error.
This creates a new statement line
that allows lines of text to be specified
without quotes.
python early:
def parse_smartline(lex):
who = lex.simple_expression()
what = lex.rest()
return (who, what)
def execute_smartline(o):
who, what = o
renpy.say(eval(who), what)
def lint_smartline(o):
who, what = o
try:
eval(who)
except:
renpy.error("Character not defined: %s" % who)
tte = renpy.check_text_tags(what)
if tte:
renpy.error(tte)
renpy.register_statement("line", parse=parse_smartline, execute=execute_smartline, lint=lint_smartline)
This can be used by writing:
line e "These quotes will show up," Eileen said, "and don't need to be backslashed."