Entry
TSE: Parser: Syntax: Analysis: Language: Visual Basic: How to parse a function? [find]
Jun 20th, 2004 14:03
Knud van Eeden,
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--- Knud van Eeden --- 20 Juny 2004 - 08:04 pm -----------------------
TSE: Parser: Syntax: Analysis: Language: Visual Basic: How to parse a
function? [find]
---
VISUAL BASIC: function: find: regular expression: string
string basic_fun[] = "^{{friend}|{private}|{public}[ \t]+}?{function}|
{sub}|{property}[ \t]"
---
VISUAL BASIC: function: regular expression: in words
A Visual Basic function
1. starts at the first character of the line
2. possibly starts with 1 word 'friend' or 'private' or 'public'
2.1 followed by 1 or more spaces or tabs,
3. followed by 1 word 'function' or 'sub' or 'property'
4. followed by 1 space or tab
---
VISUAL BASIC: function: example:
friend function TEST
private function TEST
public function TEST
friend sub TEST
private sub TEST
public sub TEST
friend property TEST
private property TEST
public property TEST
---
VISUAL BASIC: function: BNF: description:
function = begin_of_line [ ['friend' | 'private' | 'public'] (tab |
space)+ ] ('function' | 'sub' | 'property') (tab | space)
---
VISUAL BASIC: function: BNF: syntax diagram:
->-(begin of line)-------->------------------------+
|
+---------------------------------------------------+
|
|
| +---------------------->------------------------+
| | |
| | +->-(friend)->--+ +----<--------------+ |
| | | | | | |
+->-+->-+->-(private)->-+->-+->-+->-[ ]->---+->-+->-+->-+
| | | | |
+->-(public)->--+ +->-[tab]->-+ |
|
+----------------------<----------------------------+
|
|
+->-+->-(function)->-+
| |
+->-(sub)->------+->-+->-[ ]->---+->-
| | | |
+->-(property)->-+ +->-[tab]->-+
---
VISUAL BASIC: function: syntax analysis:
PROC PROCLanguageCheckFunctionComputerVisualBasicSyntaxAnalysis()
//
// ---
//
// To run:
//
// 1. Compile this macro
//
// 2. Put the cursor on the first character of the function
//
// 3. Press <F12>
//
// 4. If the cursor then moves to the end of the function name,
// it is a valid name according to the given syntax
//
// ---
//
// Example of visual basic functions:
//
// friend function TEST
//
// private function TEST
//
// public function TEST
//
// friend sub TEST
//
// private sub TEST
//
// public sub TEST
//
// friend property TEST
//
// private property TEST
//
// public property TEST
//
// ---
//
// A visual basic function
//
//
// 1. starts at the first character of the line
//
IF NOT ( CurrCol() == 1 )
Warn( 'visual basic: function: function should start at the first
position of this line' )
RETURN()
ENDIF
//
// 2. possibly starts with 1 word 'friend' or 'private' or 'public'
//
IF ( Getword() IN 'friend', 'private', 'public' )
//
// goto the end of the current word
//
EndWord()
//
// 2.1 followed by 1 or more spaces or tabs
//
WHILE ( Chr( CurrChar() ) IN ' ', Chr( 9 ) )
NextChar()
ENDWHILE
//
ENDIF
//
// 3. followed by 1 word 'function' or 'sub' or 'property'
//
IF NOT ( Getword() IN 'function', 'sub', 'property' )
Warn( 'visual basic: function: word "function" or "sub"
or "property" expected' )
ENDIF
//
// goto the end of the current word
//
EndWord()
//
// 4. followed by 1 space or tab
//
IF NOT ( Chr( CurrChar() ) IN ' ', Chr( 9 ) )
Warn( 'visual basic: function: at least 1 space or tab expected
after the word "function" or "sub" or "property"' )
RETURN()
ENDIF
//
// goto the next character
//
NextChar()
//
END
PROC Main()
PROCLanguageCheckFunctionComputerVisualBasicSyntaxAnalysis()
END
<F12> Main()
---
---
Internet: see also:
---
TSE: Parser: Syntax: Analysis: Language: Function: Can you give
overview of how to parse functions?
http://www.faqts.com/knowledge_base/view.phtml/aid/30300/fid/1236
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