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Posted to dev@velocity.apache.org by jo...@apache.org on 2001/03/12 04:25:45 UTC
cvs commit: jakarta-velocity/xdocs specification-ast.xml specification-bnf.xml specification.xml
jon 01/03/11 19:25:45
Added: xdocs specification-ast.xml specification-bnf.xml
specification.xml
Log:
moved the specification files into xdocs
Revision Changes Path
1.1 jakarta-velocity/xdocs/specification-ast.xml
Index: specification-ast.xml
===================================================================
<?xml version="1.0"?>
<document>
<properties>
<title>Velocity Specification - AST</title>
<author email="jon@latchkey.com">Velocity Documentation Team</author>
</properties>
<body>
<section name="Velocity Specification - AST">
<p>
Please note that this is currently out of date and will be updated soon.
</p>
<source><![CDATA[
This is tentatively the AST structure for Velocity.
The structure is as would be described using ANTLR
BNF-style notation. A tree is described by
#(node node node) where #() represents the tree form.
The first node is the root of the tree, and following
nodes are all children.
Visually, #(A B C D E) might look like:
A
|
B-C-D-E
Root nodes must always be a terminal node, denoted by
an all-caps identifier.
Non-root nodes may be either terminal nodes, or sub-rules,
or inlined sub-trees.
A sub-rule might describe a tree, or simple a node.
block
:
#( BLOCK
(statement)*
)
;
statement
:
text
| if_statement
| foreach_statement
| include_statement
| set_statement
| parse_statement
| param_statement
| stop_statement
| reference
;
text
:
TEXT
;
// if/elseif/else chains should be represented solely
// by <if_statement>. <elseif> is simply an <if_statement>
// in the false-branch of the preceeding <if_statement>
// while <else> is simply an <if_statement> where the
// <expr> evaluates to TRUE always, and no false-branch
// is provided.
if_statement
:
#( IF
// The expression to test
expr
// True branch
block
// False branch
( block )?
)
;
foreach_statement
:
#( FOREACH
// Value to assign for each iteration
reference
// List of objects to iterator
reference
// command-block to execute
( block )?
)
;
set_statement
:
#( SET
// Variable to set
reference
// Value to assign
expr
;
parse_statement
:
#( PARSE
STRING_LITERAL
)
;
include_statement
:
#( INCLUDE
STRING_LITERAL
)
;
stop_statement
:
STOP
;
reference
:
#( REFERENCE
postfix
;
postfix
:
method_call
|
member
|
identifier
;
member
:
#( DOT
identifier
( primary
| method_call
)
;
primary
:
IDENTIFIER
;
method_call
#( CALL
postfix
// The argument list
( expr ) *
)
;
]]></source>
</section>
</body>
</document>
1.1 jakarta-velocity/xdocs/specification-bnf.xml
Index: specification-bnf.xml
===================================================================
<?xml version="1.0"?>
<document>
<properties>
<title>Velocity Specification - BNF</title>
<author email="jon@latchkey.com">Velocity Documentation Team</author>
</properties>
<body>
<section name="Velocity Specification - BNF">
<p>
Please note that this is currently out of date and will be updated soon.
</p>
<source><![CDATA[
This is a tentative BNF for Velocity, right now this is
pretty much the WM syntax. This might change, as arithmetic
might not make it into the syntax, and the future
velocity syntax will more then likely remove block
markers and instead use an "#end" token to signify
the end of a directive.
<statement>
::= <text>
| <block>
| <if-statement>
| <else-if-statement>
| <foreach-statement>
| <include-statement>
| <set-statement>
| <parse-statement>
| <param-statment>
| <stop-statement>
| <reference>
<block>
::= "#begin" { <expresion> } "#end"
<if-statement>
::= "#if" "(" <expresion> ")" <statement> [ <else-statement> ]
<else-if-statement>
::= "#elseif" "(" <expresion> ")" <statement> [ <else-statement> ]
<foreach-statement>
::= "#foreach" <reference> "in" <reference> <statement>
<include-statement>
::= "#include" <string-literal>
<set-statement>
::= "#set" <reference> "=" <expression>
<parse-statement>
::= "#parse" <string-literal>
<param-statment>
::= "#param" <reference> "=" <string-literal>
<stop-statement>
::= "#stop"
<reference>
::= "$" <identifier> { "." <method> | <identifier> }
<method>
::= <identifier> "(" [ <parameter> { "," <parameter> } ] ")"
<parameter>
::= <reference> | <string-literal>
<alpha-char>
::= "a..z, A..Z"
<identifier-char>
::= "a..z, A..Z ,0..9 ,- ,_"
<identifier>
::= <alpha-char> { <identifier-char> }
<expression>
::= <true>
| <false>
| <primary-expression> "=" <assignment>
| <conditional-or-expression>
<assignment>
::= <primary-expression> "=" <assignment>
<conditional-or-expression>
::= <conditional-and-expression> { "||" <conditional-and-expression> }
<conditional-and-expression>
::= <equality-expression> { "&&" <equality-expression> }
<equality-expression>
::= <relational-expression>
{ "==" <relational-expression>
| "!=" <relational-expression>
}
<relational-expression>
::= <additive-expression>
{
"<" <additive-expression>
| ">" <additive-expression>
| "<=" <additive-expression>
| ">=" <additive-expression>
}
<additive-expression>
::= <multiplicative-expression>
{
"+" <multiplicative-expression>
| "-" <multiplicative-expression>
}
<multiplicative-expression>
::= <unary-expression>
{
"*" <unary-expression>
| "/" <unary-expression>
| "%" <unary-expression>
}
<unary-expression>
::= "!" <unary-expression> | <primary-expression>
<primary-expression>
::= <string-literal>
| <number-literal>
| <reference>
| "(" <expression> ")"
]]></source>
</section>
</body>
</document>
1.1 jakarta-velocity/xdocs/specification.xml
Index: specification.xml
===================================================================
<?xml version="1.0"?>
<document>
<properties>
<title>Velocity Specification</title>
<author email="jon@latchkey.com">Velocity Documentation Team</author>
</properties>
<body>
<section name="Velocity Specification">
<p>
This document will eventually describe the Velocity Specification.
For now, we have links to our outdated BNF and AST specifications.
They will be updated soon.
</p>
<ul>
<li><a href="./specification-bnf.html">BNF Specification</a></li>
<li><a href="./specification-ast.html">AST Specification</a></li>
</ul>
</section>
</body>
</document>