]]>
]]>
http://www.cnblogs.com/RicCC/archive/2008/03/17/antlr-notepad.html
http://llf.javaeye.com/blog/157507
http://llf.javaeye.com/blog/156170
]]>
| Goal | MainClass ClassDeclaration EOF | |
| MainClass | "class" Identifier "{" "public" "static" "void" "main" "(" "String" "[" "]" Identifier ")" "{" Statement "}" "}" | |
| ClassDeclaration | "class" Identifier "extends" Identifier "{" VarDeclaration MethodDeclaration "}" | |
| VarDeclaration | Type Identifier ";" | |
| MethodDeclaration | "public" Type Identifier "(" Type Identifier "," Type Identifier ")" "{" VarDeclaration Statement "return" Expression ";" "}" | |
| Type | "int" "[" "]" | |
| "boolean" | ||
| "int" | ||
| Identifier | ||
| Statement | "{" Statement "}" | |
| "if" "(" Expression ")" Statement "else" Statement | ||
| "while" "(" Expression ")" Statement | ||
| "System.out.println" "(" Expression ")" ";" | ||
| Identifier "=" Expression ";" | ||
| Identifier "[" Expression "]" "=" Expression ";" | ||
| Expression | Expression "&&" | "<" | "+" | "-" | "*" Expression | |
| Expression "[" Expression "]" | ||
| Expression "." "length" | ||
| Expression "." Identifier "(" Expression "," Expression ")" | ||
| IntegerLiteral | ||
| "true" | ||
| "false" | ||
| Identifier | ||
| "this" | ||
| "new" "int" "[" Expression "]" | ||
| "new" Identifier "(" ")" | ||
| "!" Expression | ||
| "(" Expression ")" | ||
| Identifier | one or more letters, digits, and underscores, starting with a letter | |
| IntegerLiteral | one or more decimal digits | |
| EOF | a distinguished token returned by the scanner at end-of-file |
Comments
Comments are // to end of line and /* ... */, just as in Java. The /* ... */ comments do not nest in Java. For example,/*
One commment
/* Nested comment */
Bad things will happen
*/
The second /* will be ignored (it is in a comment), and the first */ will terminate the comment. Now, "bad things will happen" as the remaining text is not a comment.
Appel, 2nd edition, page 484, describes comments in MiniJava as being nestable. This is an interesting exercise for the scanner, but is not required.
EBNF
ISO/IEC 14977: 1996(E)- Terminal symbols are quoted
- and indicate optional symbols
- and indicate repetition
- and group items together; the other brackets do too
]]>
SET_TYPES = { "bool", "char", "float", "int", "string" }
SET_LITERALS = { <boolean_literal>, <char_literal>, <float_literal>, <int_literal>, <string_literal> }
SET_INSTRUCTIONS = { "label", "break", "continue", "if", "goto", "while", "do", "switch", "return", ";" }
SET_UNARIES = { "&", "*", "~", "+", "-", "!" }
module
module: "module" <identifier> ";" globals.
globals
globals: e.
globals: global globals.
globals: "extern" global globals.
global
global: function.
global: declaration.
function
function: functionheader functionrest.
functionheader
functionheader: modifiers <identifier> ":" paramlist "->" returntype.
functionrest
functionrest: ";".
functionrest: block.
modifiers:
modifiers: e.
modifiers: "start".
paramlist
paramlist: "void".
paramlist: paramblock moreparamblocks.
moreparamblocks
moreparamblocks: e.
moreparamblocks: ";" paramblock moreparamblocks.
paramblock
paramblock: type param moreparams.
moreparams
moreparams: e.
moreparams: "," param moreparams.
param
param: reference <identifier> dimensionblock.
returntype
returntype: type reference dimensionblock.
reference
reference: e.
reference: "*" reference.
dimensionblock
dimensionblock: e.
dimensionblock: "[" "]" dimensionblock.
block
block: "{" code "}".
code
code: e.
code: block code
code: statement code.
statement
statement: "label" <identifier> ";"
statement: ";"
statement: "break" ";"
statement: "continue" ";"
statement: expression ";"
statement: declarationblock ";"
statement: "if" "(" expression ")" block elseblock
statement: "goto" <identifier> ";"
statement: "while" "(" expression ")" "do" block
statement: "do" block "while" "(" expression ")" ";"
statement: "switch" "(" expression ")" "{" switchcases "default" block "}"
statement: "return" returnarg ";".
returnarg
returnarg: "(" expression ")".
returnarg: e.
elseblock
elseblock: e.
elseblock: "else" block.
switchcases
switchcases: e.
switchcases: "case" <int_literal> block swithcases.
declarationblock
declarationblock: type declaration restdeclarations.
restdeclarations
restlocals: e.
restlocals: "," declaration restdeclarations.
declaration
local: reference <identifier> indexblock initializer.
indexblock
indexblock: e.
indexblock: "[" <int_literal> "]" indexblock.
initializer
initializer: e.
initializer: "=" expression.
expression
expression: logicalor restexpression.
restexpression
restexpression: e.
restexpression: "=" logicalor restexpression.
logicalor
logicalor: logicaland restlogicalor.
restlogicalor
restlogicalor: e.
restlogicalor: "||" logicaland restlogicalor.
logicaland
logicaland: bitwiseor restlogicaland.
restlogicaland
restlogicaland: e.
restlogicaland: "&&" bitwiseor restlogicaland.
bitwiseor
bitwiseor: bitwisexor restbitwiseor.
restbitwiseor
restbitwiseor: e.
restbitwiseor: "|" bitwisexor restbitwiseor.
bitwisexor
bitwisexor: bitwiseand restbitwisexor.
restbitwisexor
restbitwisexor: e.
restbitwisexor: "^" bitwiseand restbitwisexor.
bitwiseand
bitwiseand: equality restbitwiseand.
restbitwiseand
restbitwiseand: e.
restbitwiseand: "&" equality restbitwiseand.
equality
equality: relation restequality.
restequality
restequality: e.
restequality: equalityoperator relation restequality.
equalityoperator
equalityoperator: "==".
equalityoperator: "!=".
relation
relation: shift restrelation.
restrelation
restrelation: e.
restrelation: relationoperator shift restrelation.
relationoperator
relationoperator: "<".
relationoperator: "<=".
relationoperator: ">".
relationoperator: ">=".
shift
shift: addition restshift.
restshift
restshift: e.
restshift: shiftoperator addition restshift.
shiftoperator
shiftoperator: "<<".
shiftoperator: ">>".
addition
addition: multiplication restaddition.
restaddition
restaddition: e.
restaddition: additionoperator multiplication restaddition.
additionoperator
additionoperator: "+".
additionoperator: "-".
multiplication
multiplication: unary3 restmultiplication.
restmultiplication
restmultiplication: e.
restmultiplication: multiplicationoperator unary3 restmultiplication.
multiplicationoperator
multiplicationoperator: "*".
multiplicationoperator: "/".
multiplicationoperator: "%".
unary3
unary3: unary2
unary3: unary3operator unary3.
unary3operator:
unary3operator: "&".
unary3operator: "*".
unary3operator: "~".
unary2
unary2: factor.
unary2: unary2operator unary2.
unary2operator
unary2operator: "+".
unary2operator: "-".
unary2operator: "!".
factor
factor: <identifier> application.
factor: immediate.
factor: "(" expression ")".
application
application: e.
application: "[" expression "]" application.
application: "(" expression moreexpressions ")".
moreexpressions
moreexpressions: e.
moreexpressions: "," expression morexpressions.
type
type: "bool".
type: "char".
type: "float".
type: "int".
type: "string".
immediate
immediate: <boolean_literal>.
immediate: <char_literal>.
immediate: <float_literal>.
immediate: <int_literal>.
immediate: <string_literal>.
]]>
module
module: "module" <identifier> ";" {[extern] global}.
global
global: function | declaration.
Functions
function
function: functionheader [ ";" | block ].
functionheader
functionheader: ["start"] <identifier> ":" paramlist "->" returntype.
paramlist
paramlist: "void" | paramblock {";" paramblock}.
paramblock
paramblock: type param {"," param}.
param
param: {"*"} <identifier> {"[" "]"}.
returntype
returntype: type {"*"} {"[" "]"}.
Blocks and statements
block
block: "{" { statement | block } "}".
statement
statement: "label" <identifier> ";"
statement: ";"
statement: "break" ";"
statement: "continue" ";"
statement: expression ";"
statement: declarationblock ";"
statement: "if" "(" expression ")" block [ "else" block ].
statement: "goto" <identifier> ";"
statement: "while" "(" expression ")" "do" block
statement: "do" block "while" "(" expression ")" ";"
statement: "switch" "(" expression ")" "{" { "case" <int_literal> block } "default" block "}"
statement: "return" "(" expression ")"";".
declarationblock
declarationblock: type declaration {"," declaration}.
declaration
local: {"*"} <identifier> {"[" <int_literal> "]"} [ "=" expression ].
Expressions
Assignment
expression: logicalor {"=" logicalor expression}.
Logical OR
logicalor: logicaland {"||" logicaland logicalor}.
Logical AND
logicaland: bitwiseor {"&&" bitwiseor logicaland}.
Bitwise OR
bitwiseor: bitwisexor {"|" bitwisexor bitwiseor}.
Bitwise XOR
bitwisexor: bitwiseand {"^" bitwiseand bitwisexor}.
Bitwise AND
bitwiseand: equality {"&" equality bitwiseand}.
Equality
equality: relation {("==" | "!=") relation equality}.
Relation
relation: shift {("<" | "<=" | ">" | ">=") shift relation}.
Bitwise shift
shift: addition {("<<" | ">>") addition shift}.
Addition/subtraction
addition: multiplication {("+" | "-") multiplication addition}
Multiplication/division
multiplication: unary3 {("*" | "/" | "%") unary3 multiplication}.
Unary operations
Reference, indirection and bitwise complement
unary3: {("&" | "*" | "~")} unary2.
Unary negation, unary plus and logical NOT
unary2: {("+" | "-" | "!")} factor.
Factor and application
factor
factor: <identifier> [application] | immediate | "(" expression ")".
application
application: "[" expression "]" application | "(" expression {"," expression } ")".
Types and immediates
type
type: "bool" | "char" | "float" | "int" | "string".
immediate
immediate: <boolean_literal> | <char_literal> | <float_literal> | <int_literal> | <string_literal>.
]]>
璇嶆硶鍒嗘瀽錛?br>鍏抽敭瀛楀畾涔?
/* This enum contains all the keywords and operators
* used in the language.
*/
enum
{
/* Keywords */
KW_BREAK = 1000, /* "break" keyword */
KW_CASE, /* "case" keyword */
KW_CONTINUE, /* "continue" keyword */
KW_DEFAULT, /* "default" keyword */
KW_DO, /* "do" keyword */
KW_ELSE, /* "else" keyword */
KW_EXTERN, /* "extern" keyword */
KW_GOTO, /* "goto" keyword */
KW_IF, /* "if" keyword */
KW_LABEL, /* "label" keyword */
KW_MODULE, /* "module" keyword */
KW_RETURN, /* "return"keyword */
KW_START, /* "start" keyword */
KW_SWITCH, /* "switch" keyword */
KW_WHILE, /* "while" keyword */
/* Type identifiers */
KW_BOOL, /* "bool" identifier */
KW_CHAR, /* "char" identifier */
KW_FLOAT, /* "float" identifier */
KW_INT, /* "int" identifier */
KW_UNTYPED, /* "untyped" identifier */
KW_VOID, /* "void" identifier */
/* Variable lexer tokens */
LIT_BOOL, /* bool constant */
LIT_CHAR, /* character constant */
LIT_FLOAT, /* floating point constant */
LIT_INT, /* integer constant */
LIT_STRING, /* string constant */
IDENTIFIER, /* identifier */
/* Operators */
OP_ADD, /* "+" */
OP_ASSIGN, /* "=" */
OP_BITWISE_AND, /* "&" */
OP_BITWISE_COMPLEMENT, /* "~" */
OP_BITWISE_LSHIFT, /* "<<" */
OP_BITWISE_OR, /* "|" */
OP_BITWISE_RSHIFT, /* ">>" */
OP_BITWISE_XOR, /* "^" */
OP_DIVIDE, /* "/" */
OP_EQUAL, /* "==" */
OP_GREATER, /* ">" */
OP_GREATEREQUAL, /* ">=" */
OP_LESS, /* "<" */
OP_LESSEQUAL, /* "<=" */
OP_LOGICAL_AND, /* "&&" */
OP_LOGICAL_OR, /* "||" */
OP_MODULUS, /* "%" */
OP_MULTIPLY, /* "*" */
OP_NOT, /* "!" */
OP_NOTEQUAL, /* "!=" */
OP_SUBTRACT, /* "-" */
OP_TERNARY_IF, /* "?" */
/* Delimiters */
ARROW, /* "->" */
LBRACE, /* "{" */
RBRACE, /* "}" */
LBRACKET, /* "[" */
RBRACKET, /* "]" */
COLON, /* ":" */
COMMA, /* "," */
LPAREN, /* "(" */
RPAREN, /* ")" */
SEMICOLON /* ";" */
}
tokens;
澶勭悊inger涓殑鍚勭鏁版嵁綾誨瀷鍜屾爣璇嗙錛屽BOOL, unsigned long, float, char*,鏍囪瘑絎︾瓑
typedef union
{
unsigned long uintvalue;
BOOL boolvalue;
char *stringvalue;
char charvalue;
float floatvalue;
char *identifier;
} Tokenvalue;
鏍戣妭鐐圭粨鏋?娉ㄦ剰錛氭爲鑺傜偣鍜屾娊璞¤娉曟爲鑺傜偣鏄笉鍚岀殑)錛?br>typedef struct TreeNode
{
void *data;
int screenX;
struct TreeNode *parent;
List *children; //涓緋誨垪瀛╁瓙
} TreeNode;
鎶借薄璇硶鏍戣妭鐐圭粨鏋勶細
typedef struct AstNode
{
int id; //琛ㄧず鑺傜偣鐨勭被鍨嬶紝濡倃hile鑺傜偣錛宮odule鑺傜偣
Tokenvalue val;
Type *type;
int lineno;
} AstNode;
鎶借薄璇硶鏍戠殑AstNode浣滀負TreeNode鐨刣ata鎴愬憳淇濆瓨錛屽弬鑰冨涓嬪嚱鏁幫細
//鍙傛暟id琛ㄧず鑺傜偣鍚嶏紝濡傦細NODE_MODULE,NODE_GLOBAL絳夎nodenames.h
TreeNode *CreateAstNode( int id, int lineno )
{
TreeNode *treeNode;
AstNode *astNode;
astNode = (AstNode *) MallocEx( sizeof( AstNode ) );
astNode->id = id;
astNode->lineno = lineno;
astNode->val.uintvalue = 0;
astNode->type = NULL;
treeNode = CreateTreeNode( astNode );
return( treeNode );
}
鎴栬咃細
TreeNode *CreateAstNodeVal( int id, Tokenvalue val, int lineno )
{
TreeNode *treeNode;
AstNode *astNode;
astNode = (AstNode *) MallocEx( sizeof( AstNode ) );
astNode->id = id;
astNode->lineno = lineno;
astNode->val = val;
astNode->type = NULL;
treeNode = CreateTreeNode( astNode );
return( treeNode );
}
//鎶借薄璇硶鏍戣妭鐐瑰悕
enum NodeNames
{
NODE_MODULE = 0,
NODE_START,
NODE_EXTERN,
NODE_GLOBAL,
NODE_FUNCTION,
NODE_FUNCTIONHEADER,
NODE_MODIFIERS,
NODE_PARAMLIST,
NODE_PARAMBLOCK,
NODE_PARAM,
NODE_RETURNTYPE,
NODE_DIMENSION,
NODE_DIMENSIONBLOCK,
NODE_BLOCK,
NODE_STATEMENT,
NODE_SWITCH,
NODE_CASES,
NODE_CASE,
NODE_WHILE,
NODE_GOTO,
NODE_LABEL,
NODE_IF,
NODE_IDENT,
NODE_RETURN,
NODE_CONTINUE,
NODE_BREAK,
NODE_DECLBLOCK,
NODE_DECLARATION,
NODE_INITIALIZER,
NODE_INDEXBLOCK,
NODE_REFERENCE,
NODE_INDEX,
NODE_EXPRESSION,
NODE_LOGICAL_OR,
NODE_LOGICAL_AND,
NODE_BITWISE_OR,
NODE_BITWISE_XOR,
NODE_BITWISE_AND,
NODE_EQUAL,
NODE_NOTEQUAL,
NODE_GREATER,
NODE_GREATEREQUAL,
NODE_LESS,
NODE_LESSEQUAL,
NODE_BITWISE_LSHIFT,
NODE_BITWISE_RSHIFT,
NODE_ASSIGN,
NODE_BINARY_ADD,
NODE_BINARY_SUBTRACT,
NODE_UNARY_ADD,
NODE_UNARY_SUBTRACT,
NODE_MULTIPLY,
NODE_DIVIDE,
NODE_MODULUS,
NODE_BITWISE_COMPLEMENT,
NODE_ADDRESS,
NODE_DEREFERENCE,
NODE_NOT,
NODE_APPLICATION,
NODE_INDEXER,
NODE_ARGUMENTS,
NODE_FACTOR,
NODE_BOOL,
NODE_CHAR,
NODE_FLOAT,
NODE_INT,
NODE_UNTYPED,
NODE_VOID,
NODE_LIT_BOOL,
NODE_LIT_CHAR,
NODE_LIT_FLOAT,
NODE_LIT_INT,
NODE_LIT_STRING,
NODE_LIT_IDENTIFIER,
NODE_INT_TO_FLOAT,
NODE_CHAR_TO_INT,
NODE_CHAR_TO_FLOAT,
NODE_UNKNOWN = -1
};
杈撳嚭鎶借薄璇硶鏍戯細
/*
* PRINTING ROUTINES
*/
void PrintAst( TreeNode *source )
{
PrintTree( source, GetAstNodeData, 4 );
}
PrintTree鐨勫疄鐜板涓嬶紝榪欓噷浼犻掔殑鍙傛暟levels絳変簬4
void PrintTree( TreeNode *source, DataFunction dataFunction, int levels )
{
int printDepth = 0;
BOOL loop;
char *str;
int i;
/* TODO: We're going to have to make a new macro.
* Don't use DEBUG for this.
*/
DEBUG( "Called\n" );
/* If tree is empty, abort. */
if( source == NULL )
{
return;
}
/* Walk through tree to determine x-offsets for
* each node.
*/
LayoutTree( source, LEFT_OFFSET );
/* Print nodes. */
渚濇閫氳繃璋冪敤鍑芥暟鎸囬拡dataFunction鎵鎸囧悜鐨勫嚱鏁?瀹為檯涓婃槸鍑芥暟GetAstNodeData)
鏉ヨ緭鍑烘瘡涓妭鐐圭殑鑺傜偣鍚嶏紝鑺傜偣鐨則oken鐨勫鹼紝綾誨瀷鍚嶏紝浠ュ強琛屽彿錛屽弬鑰冧笅闈㈢殑GetAstNodeData鍑芥暟
for( i = 0; i < levels; i++ )
{
str = dataFunction( source, i );
PrintChars( source->screenX - strlen( str ) / 2, ' ' );
printf( "%s\n", str );
}
PrintChars( source->screenX, ' ' );
printf( "%c", VERTBAR );
printDepth = 0;
do
{
currentX = 0;
printf("\n");
PrintNode( source, 0, printDepth, 0, dataFunction, 0 );
currentX = 0;
printf("\n");
PrintNode( source, 0, printDepth, 1, dataFunction, 0 );
currentX = 0;
printf("\n");
for( i = 0; i < levels; i++ )
{
PrintNode( source, 0, printDepth, 2, dataFunction, i );
currentX = 0;
printf("\n");
}
loop = PrintNode( source, 0, printDepth, 3, dataFunction, 0 );
printDepth++;
}
while( loop );
}
娣誨姞涓涓瀛愮殑鎿嶄綔鍙渶瑕佸皢鏂拌妭鐐規彃鍏ュ埌瀛╁瓙閾捐〃灝鵑儴鍗沖彲
void AddTreeChild( TreeNode *parentnode, TreeNode *node )
{
/* Do not act on an empty node. */
if( node == NULL ) return;
/* If the tree is empty, add the first root node. */
if( parentnode == NULL )
{
node->parent = NULL;
}
else
/* Tree is not empty. Add the new node to [parentnode]'s
* children list. */
{
node->parent = parentnode;
ListAppend( parentnode->children, node );
}
}
鑰孯emoveAstNode鍒欏垹闄ゆ暣涓瓙鏍?br>/* Remove node [node] from ast. The node contents
* and its children get deleted.
*
* Pre: [node] is not NULL.
*/
void RemoveAstNode( TreeNode *node );
inger緙栬瘧嫻佺▼錛?br>1. 棰勫鐞嗭紝鍏抽敭鍑芥暟涓篜reprocess
2. 璇硶鍒嗘瀽錛屾瀯寤烘娊璞¤娉曟爲錛屽叧閿嚱鏁癙arse錛孭arse涔熸槸鏋勯犳娊璞¤娉曟爲鐨勫叆鍙ｅ嚱鏁幫紝濡傛灉璇硶鍒嗘瀽娌℃湁鍙戠幇閿欒鍒欒煩鍒扮3姝?br>3. 鏍規嵁鎶借薄璇硶鏍戞潵寤虹珛絎﹀彿琛ㄥ叧閿嚱鏁頒負CreateSymbolTable( ast );
4. 璇箟鍒嗘瀽錛屽叧閿嚱鏁幫細
a) CheckLeftValues( ast );
b) CheckArgCount( ast );
c) CheckSwitchStatements( ast );
d) CheckFunctionReturns( ast );
5. 鏍規嵁鎶借薄璇硶鏍戠敓鎴愪唬鐮侊紝鍏抽敭鍑芥暟GenerateCode( ast );
]]>
]]>
"
^\d+$
"
銆銆
//
闈炶礋鏁存暟錛堟鏁存暟聽+聽0錛壜?/span>
"
^[0-9]*[1-9][0-9]*$
"
銆銆
//
姝ｆ暣鏁奧?/span>
"
^((-\d+)|(0+))$
"
銆銆
//
闈炴鏁存暟錛堣礋鏁存暟聽+聽0錛壜?/span>
"
^-[0-9]*[1-9][0-9]*$
"
銆銆
//
璐熸暣鏁奧?/span>
"
^-?\d+$
"
銆銆銆銆
//
鏁存暟聽
"
^\d+(\.\d+)?$
"
銆銆
//
闈炶礋嫻偣鏁幫紙姝ｆ誕鐐規暟聽+聽0錛壜?/span>
"
^(([0-9]+\.[0-9]*[1-9][0-9]*)|([0-9]*[1-9][0-9]*\.[0-9]+)|([0-9]*[1-9][0-9]*))$
"
銆銆
//
姝ｆ誕鐐規暟聽
"
^((-\d+(\.\d+)?)|(0+(\.0+)?))$
"
銆銆
//
闈炴嫻偣鏁幫紙璐熸誕鐐規暟聽+聽0錛壜?/span>
"
^(-(([0-9]+\.[0-9]*[1-9][0-9]*)|([0-9]*[1-9][0-9]*\.[0-9]+)|([0-9]*[1-9][0-9]*)))$
"
銆銆
//
璐熸誕鐐規暟聽
"
^(-?\d+)(\.\d+)?$
"
銆銆
//
嫻偣鏁奧?/span>
"
^[A-Za-z]+$
"
銆銆
//
鐢?6涓嫳鏂囧瓧姣嶇粍鎴愮殑瀛楃涓猜?/span>
"
^[A-Z]+$
"
銆銆
//
鐢?6涓嫳鏂囧瓧姣嶇殑澶у啓緇勬垚鐨勫瓧絎︿覆聽
"
^[a-z]+$
"
銆銆
//
鐢?6涓嫳鏂囧瓧姣嶇殑灝忓啓緇勬垚鐨勫瓧絎︿覆聽
"
^[A-Za-z0-9]+$
"
銆銆
//
鐢辨暟瀛楀拰26涓嫳鏂囧瓧姣嶇粍鎴愮殑瀛楃涓猜?/span>
"
^\w+$
"
銆銆
//
鐢辨暟瀛椼?6涓嫳鏂囧瓧姣嶆垨鑰呬笅鍒掔嚎緇勬垚鐨勫瓧絎︿覆聽
"
^[\w-]+(\.[\w-]+)*@[\w-]+(\.[\w-]+)+$
"
銆銆銆銆
//
email鍦板潃聽
"
^[a-zA-z]+://(\w+(-\w+)*)(\.(\w+(-\w+)*))*(\?\S*)?$
"
銆銆
//
url
/^
(d
{
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-
((
0
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/
聽聽聽
//
聽聽騫?鏈?鏃?/span>
/^
((
0
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聽聽聽
//
聽鏈?鏃?騫?/span>
"
^([w-.]+)@(([[0-9]{1,3}.[0-9]{1,3}.[0-9]{1,3}.)|(([w-]+.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(]?)$
"
聽聽聽
//
Emil
"
(d+-)?(d{4}-?d{7}|d{3}-?d{8}|^d{7,8})(-d+)?
"
聽聽聽聽聽
//
鐢佃瘽鍙風爜
"
^(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5])$
"
聽聽聽
//
IP鍦板潃
聽
鍖歸厤涓枃瀛楃鐨勬鍒欒〃杈懼紡錛?[\u4e00-\u9fa5]
鍖歸厤鍙屽瓧鑺傚瓧絎?鍖呮嫭姹夊瓧鍦ㄥ唴)錛歔^\x00-\xff]
鍖歸厤絀鴻鐨勬鍒欒〃杈懼紡錛歕n[\s| ]*\r
鍖歸厤HTML鏍囪鐨勬鍒欒〃杈懼紡錛?<(.*)>.*<\/\1>|<(.*) \/>/
鍖歸厤棣栧熬絀烘牸鐨勬鍒欒〃杈懼紡錛?^\s*)|(\s*$)
鍖歸厤Email鍦板潃鐨勬鍒欒〃杈懼紡錛歕w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*
鍖歸厤緗戝潃URL鐨勬鍒欒〃杈懼紡錛歗[a-zA-z]+://(\\w+(-\\w+)*)(\\.(\\w+(-\\w+)*))*(\\?\\S*)?$
鍖歸厤甯愬彿鏄惁鍚堟硶(瀛楁瘝寮澶達紝鍏佽5-16瀛楄妭錛屽厑璁稿瓧姣嶆暟瀛椾笅鍒掔嚎)錛歗[a-zA-Z][a-zA-Z0-9_]{4,15}$
鍖歸厤鍥藉唴鐢佃瘽鍙風爜錛?\d{3}-|\d{4}-)?(\d{8}|\d{7})?
鍖歸厤鑵捐QQ鍙鳳細^[1-9]*[1-9][0-9]*$
涓嬭〃鏄厓瀛楃鍙婂叾鍦ㄦ鍒欒〃杈懼紡涓婁笅鏂囦腑鐨勮涓虹殑涓涓畬鏁村垪琛細
\ 灝嗕笅涓涓瓧絎︽爣璁頒負涓涓壒孌婂瓧絎︺佹垨涓涓師涔夊瓧絎︺佹垨涓涓悗鍚戝紩鐢ㄣ佹垨涓涓叓榪涘埗杞箟絎︺?br />
^ 鍖歸厤杈撳叆瀛楃涓茬殑寮濮嬩綅緗傚鏋滆緗簡 RegExp 瀵硅薄鐨凪ultiline 灞炴э紝^ 涔熷尮閰?鈥橽n鈥?鎴?鈥橽r鈥?涔嬪悗鐨勪綅緗?
$ 鍖歸厤杈撳叆瀛楃涓茬殑緇撴潫浣嶇疆銆傚鏋滆緗簡 RegExp 瀵硅薄鐨凪ultiline 灞炴э紝$ 涔熷尮閰?鈥橽n鈥?鎴?鈥橽r鈥?涔嬪墠鐨勪綅緗?
* 鍖歸厤鍓嶉潰鐨勫瓙琛ㄨ揪寮忛浂嬈℃垨澶氭銆?
+ 鍖歸厤鍓嶉潰鐨勫瓙琛ㄨ揪寮忎竴嬈℃垨澶氭銆? 絳変環浜?{1,}銆?
? 鍖歸厤鍓嶉潰鐨勫瓙琛ㄨ揪寮忛浂嬈℃垨涓嬈°? 絳変環浜?{0,1}銆?
{n} n 鏄竴涓潪璐熸暣鏁幫紝鍖歸厤紜畾鐨刵 嬈°?br />
{n,} n 鏄竴涓潪璐熸暣鏁幫紝鑷沖皯鍖歸厤n 嬈°?
{n,m} m 鍜?n 鍧囦負闈炶礋鏁存暟錛屽叾涓璶 <= m銆傛渶灝戝尮閰?n 嬈′笖鏈澶氬尮閰?m 嬈°傚湪閫楀彿鍜屼袱涓暟涔嬮棿涓嶈兘鏈夌┖鏍箋?br />
? 褰撹瀛楃绱ц窡鍦ㄤ換浣曚竴涓叾浠栭檺鍒剁 (*, +, ?, {n}, {n,}, {n,m}) 鍚庨潰鏃訛紝鍖歸厤妯″紡鏄潪璐┆鐨勩傞潪璐┆妯″紡灝藉彲鑳藉皯鐨勫尮閰嶆墍鎼滅儲鐨勫瓧絎︿覆錛岃岄粯璁ょ殑璐┆妯″紡鍒欏敖鍙兘澶氱殑鍖歸厤鎵鎼滅儲鐨勫瓧絎︿覆銆?
. 鍖歸厤闄?"\n" 涔嬪鐨勪換浣曞崟涓瓧絎︺傝鍖歸厤鍖呮嫭 鈥橽n鈥?鍦ㄥ唴鐨勪換浣曞瓧絎︼紝璇蜂嬌鐢ㄨ薄 鈥橻.\n]鈥?鐨勬ā寮忋?
(pattern) 鍖歸厤pattern 騫惰幏鍙栬繖涓鍖歸厤銆?
(?:pattern) 鍖歸厤pattern 浣嗕笉鑾峰彇鍖歸厤緇撴灉錛屼篃灝辨槸璇磋繖鏄竴涓潪鑾峰彇鍖歸厤錛屼笉榪涜瀛樺偍渚涗互鍚庝嬌鐢ㄣ?
(?=pattern) 姝ｅ悜棰勬煡錛屽湪浠諱綍鍖歸厤 pattern 鐨勫瓧絎︿覆寮濮嬪鍖歸厤鏌ユ壘瀛楃涓層傝繖鏄竴涓潪鑾峰彇鍖歸厤錛屼篃灝辨槸璇達紝璇ュ尮閰嶄笉闇瑕佽幏鍙栦緵浠ュ悗浣跨敤銆?
(?!pattern) 璐熷悜棰勬煡錛屼笌(?=pattern)浣滅敤鐩稿弽
x|y 鍖歸厤 x 鎴?y銆?
[xyz] 瀛楃闆嗗悎銆?
[^xyz] 璐熷煎瓧絎﹂泦鍚堛?
[a-z] 瀛楃鑼冨洿錛屽尮閰嶆寚瀹氳寖鍥村唴鐨勪換鎰忓瓧絎︺?
[^a-z] 璐熷煎瓧絎﹁寖鍥達紝鍖歸厤浠諱綍涓嶅湪鎸囧畾鑼冨洿鍐呯殑浠繪剰瀛楃銆?
\b 鍖歸厤涓涓崟璇嶈竟鐣岋紝涔熷氨鏄寚鍗曡瘝鍜岀┖鏍奸棿鐨勪綅緗?br />
\B 鍖歸厤闈炲崟璇嶈竟鐣屻?
\cx 鍖歸厤鐢眡鎸囨槑鐨勬帶鍒跺瓧絎︺?
\d 鍖歸厤涓涓暟瀛楀瓧絎︺傜瓑浠蜂簬 [0-9]銆?
\D 鍖歸厤涓涓潪鏁板瓧瀛楃銆傜瓑浠蜂簬 [^0-9]銆?
\f 鍖歸厤涓涓崲欏電銆傜瓑浠蜂簬 \x0c 鍜?\cL銆?
\n 鍖歸厤涓涓崲琛岀銆傜瓑浠蜂簬 \x0a 鍜?\cJ銆?
\r 鍖歸厤涓涓洖杞︾銆傜瓑浠蜂簬 \x0d 鍜?\cM銆?
\s 鍖歸厤浠諱綍絀虹櫧瀛楃錛屽寘鎷┖鏍箋佸埗琛ㄧ銆佹崲欏電絳夌瓑銆傜瓑浠蜂簬[ \f\n\r\t\v]銆?
\S 鍖歸厤浠諱綍闈炵┖鐧藉瓧絎︺傜瓑浠蜂簬 [^ \f\n\r\t\v]銆?
\t 鍖歸厤涓涓埗琛ㄧ銆傜瓑浠蜂簬 \x09 鍜?\cI銆?
\v 鍖歸厤涓涓瀭鐩村埗琛ㄧ銆傜瓑浠蜂簬 \x0b 鍜?\cK銆?
\w 鍖歸厤鍖呮嫭涓嬪垝綰跨殑浠諱綍鍗曡瘝瀛楃銆傜瓑浠蜂簬鈥橻A-Za-z0-9_]鈥欍?
\W 鍖歸厤浠諱綍闈炲崟璇嶅瓧絎︺傜瓑浠蜂簬 鈥橻^A-Za-z0-9_]鈥欍?
\xn 鍖歸厤 n錛屽叾涓?n 涓哄崄鍏繘鍒惰漿涔夊箋傚崄鍏繘鍒惰漿涔夊煎繀欏諱負紜畾鐨勪袱涓暟瀛楅暱銆?br />
\num 鍖歸厤 num錛屽叾涓璶um鏄竴涓鏁存暟銆傚鎵鑾峰彇鐨勫尮閰嶇殑寮曠敤銆?
\n 鏍囪瘑涓涓叓榪涘埗杞箟鍊兼垨涓涓悗鍚戝紩鐢ㄣ傚鏋?\n 涔嬪墠鑷沖皯 n 涓幏鍙栫殑瀛愯〃杈懼紡錛屽垯 n 涓哄悗鍚戝紩鐢ㄣ傚惁鍒欙紝濡傛灉 n 涓哄叓榪涘埗鏁板瓧 (0-7)錛屽垯 n 涓轟竴涓叓榪涘埗杞箟鍊箋?
\nm
鏍囪瘑涓涓叓榪涘埗杞箟鍊兼垨涓涓悗鍚戝紩鐢ㄣ傚鏋?\nm 涔嬪墠鑷沖皯鏈塱s preceded by at least nm 涓幏鍙栧緱瀛愯〃杈懼紡錛屽垯 nm
涓哄悗鍚戝紩鐢ㄣ傚鏋?\nm 涔嬪墠鑷沖皯鏈?n 涓幏鍙栵紝鍒?n 涓轟竴涓悗璺熸枃瀛?m 鐨勫悗鍚戝紩鐢ㄣ傚鏋滃墠闈㈢殑鏉′歡閮戒笉婊¤凍錛岃嫢 n 鍜?m
鍧囦負鍏繘鍒舵暟瀛?(0-7)錛屽垯 \nm 灝嗗尮閰嶅叓榪涘埗杞箟鍊?nm銆?
\nml 濡傛灉 n 涓哄叓榪涘埗鏁板瓧 (0-3)錛屼笖 m 鍜?l 鍧囦負鍏繘鍒舵暟瀛?(0-7)錛屽垯鍖歸厤鍏繘鍒惰漿涔夊?nml銆?
\un 鍖歸厤 n錛屽叾涓?n 鏄竴涓敤鍥涗釜鍗佸叚榪涘埗鏁板瓧琛ㄧず鐨刄nicode瀛楃銆?
鍖歸厤涓枃瀛楃鐨勬鍒欒〃杈懼紡錛?[u4e00-u9fa5]
鍖歸厤鍙屽瓧鑺傚瓧絎?鍖呮嫭姹夊瓧鍦ㄥ唴)錛歔^x00-xff]
搴旂敤錛氳綆楀瓧絎︿覆鐨勯暱搴︼紙涓涓弻瀛楄妭瀛楃闀垮害璁?錛孉SCII瀛楃璁?錛?/p>
String.prototype.len=function(){return this.replace([^x00-xff]/g,"aa").length;}
鍖歸厤絀鴻鐨勬鍒欒〃杈懼紡錛歯[s| ]*r
鍖歸厤HTML鏍囪鐨勬鍒欒〃杈懼紡錛?<(.*)>.*</1>|<(.*) />/
鍖歸厤棣栧熬絀烘牸鐨勬鍒欒〃杈懼紡錛?^s*)|(s*$)
搴旂敤錛歫avascript涓病鏈夊儚vbscript閭ｆ牱鐨則rim鍑芥暟錛屾垜浠氨鍙互鍒╃敤榪欎釜琛ㄨ揪寮忔潵瀹炵幇錛屽涓嬶細
String.prototype.trim = function()
{
return this.replace(/(^s*)|(s*$)/g, "");
}
鍒╃敤姝ｅ垯琛ㄨ揪寮忓垎瑙ｅ拰杞崲IP鍦板潃錛?/p>
涓嬮潰鏄埄鐢ㄦ鍒欒〃杈懼紡鍖歸厤IP鍦板潃錛屽茍灝咺P鍦板潃杞崲鎴愬搴旀暟鍊肩殑Javascript紼嬪簭錛?/p>
function IP2V(ip)
{
re=/(d+).(d+).(d+).(d+)/g //鍖歸厤IP鍦板潃鐨勬鍒欒〃杈懼紡
if(re.test(ip))
{
return RegExp.$1*Math.pow(255,3))+RegExp.$2*Math.pow(255,2))+RegExp.$3*255+RegExp.$4*1
}
else
{
throw new Error("Not a valid IP address!")
}
}
涓嶈繃涓婇潰鐨勭▼搴忓鏋滀笉鐢ㄦ鍒欒〃杈懼紡錛岃岀洿鎺ョ敤split鍑芥暟鏉ュ垎瑙ｅ彲鑳芥洿綆鍗曪紝紼嬪簭濡備笅錛?/p>
var ip="10.100.20.168"
ip=ip.split(".")
alert("IP鍊兼槸錛?+(ip[0]*255*255*255+ip[1]*255*255+ip[2]*255+ip[3]*1))
鍖歸厤Email鍦板潃鐨勬鍒欒〃杈懼紡錛歸+([-+.]w+)*@w+([-.]w+)*.w+([-.]w+)*
鍖歸厤緗戝潃URL鐨勬鍒欒〃杈懼紡錛歨ttp://([w-]+.)+[w-]+(/[w- ./?%&=]*)?
鍒╃敤姝ｅ垯琛ㄨ揪寮忓幓闄ゅ瓧涓蹭腑閲嶅鐨勫瓧絎︾殑綆楁硶紼嬪簭錛?/p>
var s="abacabefgeeii"
var s1=s.replace(/(.).*1/g,"$1")
var re=new RegExp("["+s1+"]","g")
var s2=s.replace(re,"")
alert(s1+s2) //緇撴灉涓猴細abcefgi
鎴戝師鏉ュ湪CSDN涓婂彂璐村姹備竴涓〃杈懼紡鏉ュ疄鐜板幓闄ら噸澶嶅瓧絎︾殑鏂規硶錛屾渶緇堟病鏈夋壘鍒幫紝榪欐槸鎴戣兘鎯沖埌鐨勬渶綆鍗曠殑瀹炵幇鏂規硶銆傛濊礬鏄嬌鐢ㄥ悗鍚戝紩鐢ㄥ彇鍑哄寘鎷噸澶嶇殑瀛楃錛屽啀浠ラ噸澶嶇殑瀛楃寤虹珛絎簩涓〃杈懼紡錛屽彇鍒頒笉閲嶅鐨勫瓧絎︼紝涓よ呬覆榪炪傝繖涓柟娉曞浜庡瓧絎﹂『搴忔湁瑕佹眰鐨勫瓧絎︿覆鍙兘涓嶉傜敤銆?/p>
寰楃敤姝ｅ垯琛ㄨ揪寮忎粠URL鍦板潃涓彁鍙栨枃浠跺悕鐨刯avascript紼嬪簭錛屽涓嬬粨鏋滀負page1
s="http://www.9499.net/page1.htm"
s=s.replace(/(.*/){0,}([^.]+).*/ig,"$2")
alert(s)
鍒╃敤姝ｅ垯琛ㄨ揪寮忛檺鍒剁綉欏佃〃鍗曢噷鐨勬枃鏈杈撳叆鍐呭錛?/p>
鐢? 姝ｅ垯琛ㄨ揪寮忛檺鍒跺彧鑳借緭鍏ヤ腑鏂囷細onkeyup="value=value.replace(/[^u4E00-u9FA5]/g,'')" onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^u4E00-u9FA5]/g,''))"
鐢? 姝ｅ垯琛ㄨ揪寮忛檺鍒跺彧鑳借緭鍏ュ叏瑙掑瓧絎︼細 onkeyup="value=value.replace(/[^uFF00-uFFFF]/g,'')" onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^uFF00-uFFFF]/g,''))"
鐢? 姝ｅ垯琛ㄨ揪寮忛檺鍒跺彧鑳借緭鍏ユ暟瀛楋細onkeyup="value=value.replace(/[^d]/g,'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^d]/g,''))"
鐢? 姝ｅ垯琛ㄨ揪寮忛檺鍒跺彧鑳借緭鍏ユ暟瀛楀拰鑻辨枃錛歰nkeyup="value=value.replace(/[W]/g,'') "onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^d]/g,''))"
]]>
]]>
]]>
]]>
]]>
鍏堢畝鍗曡鍑犲彞, 浠庝唬鐮佷笂鐪嬶紝inger浠ｇ爜娓呮櫚錛屼紭緹庯紝娉ㄩ噴鍏呰凍錛屾槸闅懼緱鐨勯槄璇誨垎鏋愪匠鍝併?br />
鏁翠釜緙栬瘧鍣ㄤ嬌鐢╟璇█緙栧啓錛屼粠闅懼害鍜屾竻鏅板害鏉ョ湅錛屾槸鎴戣榪囩殑鏈婕備寒鐨刢浠ｇ爜(瀹為檯涓婃垜璇昏繃鐨勪唬鐮佸緢灝戯紝姹?錛?br />
璇嶆硶鍒嗘瀽閮ㄥ垎浣跨敤浜唋ex銆傚ソ鍍忎篃涓嶆瘮鎵嬪啓杞繪澗澶氬皯^_^
]]>
褰撹瘝娉曞垎鏋愬櫒涓庤鏄庢枃浠惰鍒欓儴鍒嗕腑鐨勪竴涓墿灞曟鍒欒〃杈懼紡鍖歸厤鏃訛紝瀹冩墽琛屼笌鎵╁睍姝ｅ垯琛ㄨ揪寮忕浉瀵瑰簲鐨?em>鎿嶄綔銆傛病鏈夎凍澶熺殑瑙勫垯鍖歸厤杈撳叆嫻佷腑鐨勬墍鏈夊瓧絎︿覆錛岃瘝娉曞垎鏋愬櫒鍒欏皢杈撳叆澶嶅埗鍒版爣鍑嗚緭鍑恒傚洜姝わ紝涓嶈鍒涘緩浠呭皢杈撳叆澶嶅埗鍒拌緭鍑虹殑瑙勫垯銆傜己鐪佺殑杈撳嚭鑳藉甯姪鍦ㄨ鍒欎腑鏌ユ壘闂撮殧銆?/p>
褰撲嬌鐢?lex 鍛戒護澶勭悊鐢?yacc 鍛戒護浜х敓鐨勮В鏋愬櫒鐨勮緭鍏ユ椂錛岃鎻愪緵涓庢墍鏈夎緭鍏ュ瓧絎︿覆鍖歸厤鐨勮鍒欍傞偅浜涜鍒欏繀欏葷敓鎴?yacc 鍛戒護鑳藉瑙ｉ噴鐨勮緭鍑恒?/p>
絀烘搷浣?/h3>
瑕佸拷鐣ヤ笌鎵╁睍姝ｅ垯琛ㄨ揪寮忓叧鑱旂殑杈撳叆錛岃浣跨敤 ;錛圕 璇█絀鴻鍙ワ級浣滀負鎿嶄綔銆備笅闈㈢殑紺轟緥蹇界暐浜嗕笁涓棿闅斿瓧絎︼紙絀虹櫧銆佸埗琛ㄧ鍜屾崲琛岋級錛?/p>
[ \t\n] ;
涓庝笅涓涓搷浣滅浉鍚?/h3>
瑕侀伩鍏嶅弽澶嶅啓鐩稿悓鐨勬搷浣滐紝璇蜂嬌鐢?|錛堢閬撶鍙鳳級銆傛瀛楃鎸囩ず姝よ鍒欑殑鎿嶄綔涓庝笅涓鏉¤鍒欑殑鎿嶄綔鐩稿悓銆備緥濡傦紝鍏堝墠蹇界暐絀虹櫧銆佸埗琛ㄧ鍜屾崲琛屽瓧絎︾殑紺轟緥涔熷彲鍐欐垚錛?/p>
" " | "\t" | "\n" ;
鎵撳嵃鍖歸厤瀛楃涓?/h3>
瑕佺‘瀹氬摢涓枃鏈笌璇存槑鏂囦歡鐨勮鍒欓儴鍒嗙殑琛ㄨ揪寮忓尮閰嶏紝鎮ㄥ彲浠ュ寘鎵?C 璇█ printf 瀛愪緥紼嬭皟鐢ㄤ綔涓鴻琛ㄨ揪寮忕殑涓涓搷浣溿傚綋璇嶆硶鍒嗘瀽鍣ㄥ湪杈撳叆嫻佷腑鎵懼埌鍖歸厤錛岀▼搴忓皢鍖歸厤瀛楃涓叉斁鍏ュ閮ㄥ瓧絎︼紙char錛夊拰瀹藉瓧絎︼紙wchar_t錛夋暟緇勪腑錛屽垎鍒О涓?yytext 鍜?yywtext銆備緥濡傦紝鎮ㄨ兘浣跨敤涓嬮潰鐨勮鍒欐墦鍗板尮閰嶅瓧絎︿覆錛?/p>
[a-z]+ printf("%s",yytext);
C 璇█ printf 瀛愪緥紼嬫帴鍙楁牸寮忓弬鏁板拰瑕佹墦鍗扮殑鏁版嵁銆傚湪姝ょず渚嬩腑錛?strong>printf 瀛愪緥紼嬬殑鍙傛暟鍏鋒湁涓嬮潰鐨勫惈涔夛細
| %s | 鍦ㄦ墦鍗頒箣鍓嶅皢鏁版嵁杞崲涓虹被鍨嬪瓧絎︿覆鐨勭鍙?/td> |
| %S | 鍦ㄦ墦鍗頒箣鍓嶅皢鏁版嵁杞崲涓哄瀛楃涓詫紙wchar_t錛夌殑絎﹀彿 |
| yytext | 鍖呭惈瑕佹墦鍗扮殑鏁版嵁鐨勬暟緇勭殑鍚嶇О |
| yywtext | 鍖呭惈瑕佹墦鍗扮殑澶氬瓧鑺傜被鍨嬶紙wchar_t錛夋暟鎹殑鏁扮粍鍚嶇О |
lex 鍛戒護瀹氫箟 ECHO錛涗綔涓鴻鎵撳嵃 yytext 鐨勫唴瀹圭殑鐗規畩鎿嶄綔銆備緥濡傦紝涓嬮潰鐨勪袱鏉¤鍒欐槸絳変環鐨勶細
[a-z]+ ECHO;
[a-z]+ printf("%s",yytext);
鎮ㄥ彲浠ュ湪 lex 璇存槑鏂囦歡鐨勫畾涔夐儴鍒嗕嬌鐢?%array 鎴栬?%pointer 濡備笅鏇存敼 yytext 鐨勮鏄庯細
| %array | 灝?yytext 瀹氫箟涓轟互 null 緇撴潫鐨勫瓧絎︽暟緇勩傝繖鏄己鐪佹搷浣溿?/td> |
| %pointer | 灝?yytext 瀹氫箟涓烘寚鍚戜互 null 緇撴潫鐨勫瓧絎︿覆鐨勬寚閽堛?/td> |
鏌ユ壘鍖歸厤瀛楃涓茬殑闀垮害
瑕佹煡鎵捐瘝娉曞垎鏋愬櫒涓庣壒瀹氱殑鎵╁睍姝ｅ垯琛ㄨ揪寮忔墍鍖歸厤鐨勫瓧絎︽暟錛岃浣跨敤 yyleng 鎴栬?yywleng 澶栭儴鍙橀噺銆?/p>
| yyleng | 璺熻釜鍖歸厤鐨勫瓧鑺傛暟銆?/td> |
| yywleng | 璺熻釜鍖歸厤瀛楃涓蹭腑鐨勫瀛楃鏁般傚瀛楄妭瀛楃鐨勯暱搴﹀ぇ浜?1銆?/td> |
瑕佸杈撳叆鐨勫瓧鏁板拰瀛椾腑鐨勫瓧絎︽暟榪涜璁℃暟錛岃浣跨敤涓嬮潰鐨勬搷浣滐細
[a-zA-Z]+ {words++;chars += yyleng;}
姝ゆ搷浣滄昏鍖歸厤鐨勫瓧涓殑瀛楃鏁幫紝騫跺皢璇ユ暟瀛楄祴浜?chars銆?/p>
涓嬮潰鐨勮〃杈懼紡鍦ㄥ尮閰嶅瓧絎︿覆涓煡鎵炬渶鍚庝竴涓瓧絎︼細
yytext[yyleng-1]
鍖歸厤瀛楃涓蹭腑鐨勫瓧絎︿覆
lex 鍛戒護瀵硅緭鍏ユ祦榪涜鍒嗗尯錛屽茍涓嶆悳绱㈡瘡涓〃杈懼紡鐨勬墍鏈夊彲鑳界殑鍖歸厤瀛楃涓層傛瘡涓瓧絎︿粎璁＄畻涓嬈°傝瑕嗙洊姝ら夐」騫舵悳绱㈠彲鑳介噸鍙犳垨鑰呬簰鐩稿寘鍚殑欏癸紝璇蜂嬌鐢?REJECT 鎿嶄綔銆備緥濡傦紝瑕佸 she 鍜?he 鐨勬墍鏈夊疄渚嬶紙鍖呮嫭鍖呭惈鍦?she 涓殑 he錛夎鏁幫紝璇蜂嬌鐢ㄤ笅闈㈢殑鎿嶄綔錛?/p>
she {s++; REJECT;}
he {h++}
\n |. ;
鍦ㄥ she 鐨勫嚭鐜版鏁拌繘琛岃鏁板悗錛?strong>lex 鍛戒護鎷掔粷杈撳叆瀛楃涓詫紝鐒跺悗瀵?he 鐨勫嚭鐜版鏁拌繘琛岃鏁般傚洜涓?he 騫朵笉鍖呮嫭 she錛屾墍浠?REJECT 鎿嶄綔涓嶅繀鍦?he 涓娿?/p>
灝嗙粨鏋滄坊鍔犲埌 yytext 鏁扮粍
鍏稿瀷鎯呭喌涓嬶紝鏉ヨ嚜杈撳叆嫻佺殑涓嬩竴涓瓧絎︿覆瑕嗙洊 yytext 鏁扮粍涓殑褰撳墠欏廣傚鏋滄偍浣跨敤 yymore 瀛愪緥紼嬶紝鏉ヨ嚜杈撳叆嫻佺殑涓嬩竴涓瓧絎︿覆灝嗚娣誨姞鍒?yytext 鏁扮粍鐨勫綋鍓嶉」鐨勫熬閮ㄣ?/p>
%s instring
%%
<INITIAL>\" { /* start of string */
BEGIN instring;
yymore();
}
<instring>\" { /* end of string */
printf("matched %s\n", yytext);
BEGIN INITIAL;
}
<instring>. {
yymore();
}
<instring>\n {
printf("Error, new line in string\n");
BEGIN INITIAL;
}
灝界閫氳繃鍖歸厤澶氫釜瑙勫垯錛屽瓧絎︿覆鍙兘琚瘑鍒紝浣嗘槸鍙嶅璋冪敤 yymore 瀛愪緥紼嬪彲浠ョ‘淇?yytext 鏁扮粍鍖呭惈鏁翠釜瀛楃涓層?/p>
灝嗗瓧絎﹁繑鍥炲埌杈撳叆嫻?/h3>
瑕佸皢瀛楃榪斿洖緇欒緭鍏ユ祦錛岃浣跨敤涓嬮潰鐨勮皟鐢細
yyless(n)
鍏朵腑 n 鏄綋鍓嶅瓧絎︿覆涓淇濇寔鐨勫瓧絎︽暟銆傚瓧絎︿覆涓秴榪囨鏁扮洰鐨勫瓧絎﹁榪斿洖鍒拌緭鍏ユ祦銆?strong>yyless 瀛愪緥紼嬫彁渚涚殑鍏堣鍑芥暟綾誨瀷涓?/錛堟枩鏉狅級榪愮畻絎︽墍浣跨敤鐨勭浉鍚岋紝浣嗘槸瀹冨厑璁告洿澶氬鍏剁敤娉曠殑鎺у埗銆?/p>
涓嶆涓嬈′嬌鐢?yyless 瀛愪緥紼嬪鐞嗘枃鏈備緥濡傦紝褰撹娉曞垎鏋?C 璇█紼嬪簭鏃訛紝璇稿 x=-a 涔嬬被鐨勮〃杈懼紡寰堥毦鐞嗚В銆傚畠琛ㄧず x絳変簬-a錛岃繕鏄?x -= a 鐨勬棫鐨勮〃榪板艦寮忥紙鎰忓懗鐫灝?x鍑忓幓鍊?/em>a錛夛紵瑕佸皢姝よ〃杈懼紡浣滀負 x絳変簬-a 澶勭悊錛屼絾鏄鎵撳嵃璀﹀憡娑堟伅鍒欒浣跨敤濡備笅鐨勮鍒欙細
=-[a-zA-Z] {
printf("Operator (=-) ambiguous\n");
yyless(yyleng-1);
... action for = ...
}
杈撳叆錛忚緭鍑哄瓙渚嬬▼
lex 紼嬪簭鍏佽紼嬪簭浣跨敤涓嬭堪杈撳叆錛忚緭鍑猴紙I/O錛夊瓙渚嬬▼錛?/p>
lex 紼嬪簭鎻愪緵榪欎簺瀛愪緥紼嬩綔涓哄畯瀹氫箟銆傚瓙渚嬬▼鐨勪唬鐮佸湪 lex.yy.c 鏂囦歡涓傛偍鑳借鐩栧畠浠茍鎻愪緵鍏朵粬鐗堟湰銆?/p>
瀹氫箟 winput銆?strong>wunput 鍜?woutput 瀹忎互浣跨敤 yywinput銆?strong>yywunput 鍜?yywoutput 瀛愪緥紼嬨傝冭檻鍒板吋瀹規э紝yy 瀛愪緥紼嬮殢鍚庝嬌鐢?input銆?strong>unput 鍜?output 瀛愪緥紼嬫潵璇匯佸啓鍜屾浛鎹㈠畬鍏ㄥ瀛楄妭瀛楃涓渶瑕佹暟鐩殑瀛楄妭銆?/p>
榪欎簺瀛愪緥紼嬪畾涔夊閮ㄦ枃浠跺拰鍐呴儴瀛楃涔嬮棿鐨勫叧緋匯傚鏋滄偍鏇存敼瀛愪緥紼嬶紝璇蜂互鐩稿悓鐨勬柟寮忓皢瀹冧滑鍏ㄩ儴鏇存敼銆傝繖浜涘瓙渚嬬▼搴旇閬靛驚榪欎簺瑙勫垯錛?/p>
- 鎵鏈夌殑瀛愪緥紼嬪繀欏諱嬌鐢ㄧ浉鍚岀殑瀛楃闆嗐?
- input 瀛愪緥紼嬪繀欏昏繑鍥?0 鍊間互鎸囩ず鏂囦歡鐨勬湯灝俱?
- 涓嶈鏇存敼 unput 瀛愪緥紼嬪拰 input 瀛愪緥紼嬬殑鍏崇郴錛屽惁鍒欏厛琛屽嚱鏁頒細涓嶈搗浣滅敤銆?/li>
lex.yy.c 鏂囦歡鍏佽璇嶆硶鍒嗘瀽鍣ㄦ渶澶氬浠?200 涓瓧絎︺?/p>
瑕佽鍖呭惈 NULL 鐨勬枃浠訛紝璇峰垱寤轟笉鍚岀増鏈殑 input 瀛愪緥紼嬨傚湪 input 瀛愪緥紼嬬殑姝ｅ父鐗堟湰涓紝錛堜粠絀哄瓧絎︼級榪斿洖鐨勫?0 琛ㄦ槑榪欐槸鏂囦歡鐨勬湯灝撅紝涓斿皢緇堟杈撳叆銆?/p>
瀛楃闆?/h3>
lex 鍛戒護鐢熸垚鐨勮瘝娉曞垎鏋愬櫒閫氳繃 input銆乷utput 鍜?unput 瀛愪緥紼嬪鐞嗗瓧絎?I/O銆傚洜姝わ紝瑕佸湪 yytext 瀛愪緥紼嬩腑榪斿洖鍊鹼紝lex 鍛戒護浣跨敤榪欎簺瀛愪緥紼嬩嬌鐢ㄧ殑瀛楃璇存槑銆備絾鏄紝鍦ㄥ唴閮?lex 鍛戒護浣跨敤灝忔暣鏁頒唬琛ㄦ瘡涓涓瓧絎︺傚綋浣跨敤鏍囧噯搴撴椂錛屾鏁存暟鏄綆楁満鐢ㄦ潵琛ㄧず瀛楃鐨勪綅妯″紡鐨勫箋傛甯告儏鍐典笅錛屽瓧姣?a 鐢ㄤ笌瀛楃甯擱噺 a 鐩稿悓鐨勬牸寮忚〃紺恒傚鏋滄偍浣跨敤涓嶅悓鐨?I/O 瀛愪緥紼嬫洿鏀規瑙ｉ噴錛岃灝嗚漿鎹㈣〃鏀懼埌璇存槑鏂囦歡鐨勫畾涔夐儴鍒嗐傝漿鎹㈣〃鍦ㄥ寘鍚笅榪版潯鐩殑琛屽紑濮嬪拰緇撴潫錛?/p>
%T
杞崲琛ㄥ寘鍚寚紺轟笌姣忎釜瀛楃鍏寵仈鐨勫肩殑鍏朵粬琛屻備緥濡傦細
%T
{integer} {character string}
{integer} {character string}
{integer} {character string}
%T
鏂囦歡鏈熬澶勭悊
褰撹瘝娉曞垎鏋愬櫒鍒拌揪鏂囦歡鏈熬鏃訛紝瀹冭皟鐢?yywrap 搴撳瓙渚嬬▼錛屾璋冪敤榪斿洖鍊?1錛屾寚紺鴻瘝娉曞垎鏋愬櫒搴旇緇х畫鍦ㄨ緭鍏ユ湯灝炬甯哥粨鏉熴?/p>
浣嗘槸錛屽鏋滆瘝娉曞垎鏋愬櫒浠庡涓簮鎺ユ敹鍒拌緭鍏ワ紝璇鋒洿鏀?yywrap 瀛愪緥紼嬨傛柊鐨勫嚱鏁板繀欏昏幏鍙栨柊鐨勮緭鍏ュ茍灝嗗?0 榪斿洖緇欒瘝娉曞垎鏋愬櫒銆傝繑鍥炲?0 鎸囩ず紼嬪簭搴旇緇х畫澶勭悊銆?/p>
鎮ㄤ篃鍙互鍖呭惈浠ｇ爜錛屼互鍦ㄨ瘝娉曞垎鏋愬櫒鍦ㄦ柊鐗堟湰鐨?yywrap 瀛愪緥紼嬩腑緇堟鏃訛紝鎵撳嵃鎽樿鎶ュ憡鍜岃〃銆?strong>yywrap 瀛愪緥紼嬫槸寮哄埗 yylex 瀛愪緥紼嬭瘑鍒緭鍏ユ湯灝劇殑鍞竴閫斿緞銆?/p>
鏇村ソ鐨勫姙娉曟槸瀹氫箟:
int yywrap()
{聽
聽聽聽return(1);
}
鍏充簬yywrap鏇磋緇嗙殑淇℃伅鍙互鍙傝僽nix鐨刲ex manual
http://www.scit.wlv.ac.uk/cgi-bin/mansec?1+lex
int yywrap(void)
聽聽聽聽聽聽聽聽聽聽 Called by yylex at聽 end-of-file;聽 the聽 default聽 yywrap
聽聽聽聽聽聽聽聽聽聽 always聽 will聽 return聽 1.聽 If聽 the application requires
聽聽聽聽聽聽聽聽聽聽 yylex to continue processing with聽 another聽 source聽 of
聽聽聽聽聽聽聽聽聽聽 input,聽 then聽 the聽 application聽 can include a function
聽聽聽聽聽聽聽聽聽聽 yywrap, which associates another file with the聽 exter-
聽聽聽聽聽聽聽聽聽聽 nal聽 variable聽 FILE聽 *yyin聽 and will return a value of
聽聽聽聽聽聽聽聽聽聽 zero.
鎴杅lex鐨勫弬鑰冩墜鍐?榪欎釜璨屼技鏇村箍娉涗竴鐐?錛?br />http://www.gnu.org/software/flex/manual/html_mono/flex.html
When the scanner receives an end-of-file indication from YY_INPUT, it then checks the `yywrap()' function. If `yywrap()' returns false (zero), then it is assumed that the function has gone ahead and set up yyin to point to another input file, and scanning continues. If it returns true (non-zero), then the scanner terminates, returning 0 to its caller. Note that in either case, the start condition remains unchanged; it does not revert to INITIAL.
If you do not supply your own version of `yywrap()', then you must either use `%option noyywrap' (in which case the scanner behaves as though `yywrap()' returned 1), or you must link with `-lfl' to obtain the default version of the routine, which always returns 1.
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