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--- language_definition [2012/02/26 15:54] – [Constants] mhwang
+++ language_definition [2012/03/17 08:56] (current) – [新语言与C/Pascal/Java的比较] marong
@@ Line 2: / Line 2: @@
   * [[contributed_functions|Contributed functions]]
   * [[the_eight_queens_solver|The eight queens solver]]
-  * calculator of pi
+  * [[pi_calculator|calculator of pi]]
 ====== 新语言与C/Pascal/Java的比较 ======
@@ Line 15: / Line 15: @@
 | 变量声明      || 任意块开始处      | 函数开始处       | 任意位置        | 函数开始处       |
 | 多维数组      || 连续存储空间 | 连续存储空间 | 数组的数组 | 数组的数组 |
+| 注释      || 非嵌套 | 嵌套 | 非嵌套 | 嵌套 |
+改进的建议（这学期不适用）
+. 允许全局变量
+. 函数，变量，类型有独立的名字空间
+. 变量将强制初始化
+. 变量可以在块中间声明
+. 去掉break和continue
+. 去掉逗号表达式
+---by marong
 ====== Lexical Aspects ======
 A //token// can be a keyword, an identifier, a integer constant, a character constant, or a string constant.
 Tokens are separated by whitespaces and comments.
-An //identifier// is a sequence of letters, digits, or underscores, which begins with a letter, and does not share its name with a keyword.
+An //identifier// is a sequence of letters, digits, or underscores, which begins with a letter and does not share its name with a keyword.
-Case is significant in identifiers.
+Note that (i) identifiers cannot start with underscores, and (ii) case is significant in identifiers.
 //Line terminators// are ''\n'', ''\r'', and ''\r\n''.
@@ Line 29: / Line 46: @@
 There are two types of comments: line comments and block comments.
-//Line comments// starts with two slashes ''/ /'' FIXME. Texts behind the two slashes are ignored, until a line terminator is met.
+//Line comments// starts with two slashes ''/''''/''. Texts behind the two slashes are ignored, until a line terminator is met.
-//Block comments// starts with a ''/*'', and ends with a ''*/''. Texts in between are ignored. Block comments may nest.
+//Block comments// starts with a ''/*'' and ends with a ''*/''. Texts in between are ignored. Block comments may nest.
 =====Constants=====
@@ Line 37: / Line 54: @@
 There are no negative integer constants.
-A //character constant// is one printable character, or escape sequences that represents one character, surrounded by a pair of single quotes '''''.
+A //character constant// is one printable character or space, or escape sequences that represents one character, surrounded by a pair of single quotes '''''.
-A //string constant// is a sequence of zero or more printable characters, spaces, or escape sequences, surrounded by a pair of double quotes ''"'' FIXME.
+A //string constant// is a sequence of zero or more printable characters, spaces, or escape sequences, surrounded by a pair of double quotes ''"''.
 Escape sequences begins with a backslash ''\'', and represent some special characters. Escape sequences are
@@ Line 48: / Line 65: @@
 | ''\\'' | Backslash |
 | ''\//ddd//'' | The character with ASCII code //ddd// (three decimal digits) |
-| ''\"'' FIXME | Double quote (**only allowed in a string constant**) |
+| ''\"'' | Double quote (**only allowed in a string constant**) |
 | ''\''' | Single quote (**only allowed in a character constant**) |
@@ Line 57: / Line 74: @@
 | '';'' | ''['' | '']'' | ''{'' | ''}'' | ''('' | '')'' |
 | '','' | ''='' | ''||'' | ''&&'' | ''=='' | ''!='' | ''<'' |
-| ''<='' FIXME | ''>'' | ''>='' | ''+'' | ''-'' | ''*'' | ''/'' |
+| ''<''''='' | ''>'' | ''>='' | ''+'' | ''-'' | ''*'' | ''/'' |
 | ''%'' | ''!'' | ''.'' |
@@ Line 64: / Line 81: @@
   * ''**native** **int** readInt();''
   * ''**native** **char** readChar();''
-  * ''**native** **string** readString();''
-  * ''**native** **string** readLine();''
   * ''**native** **int** printInt(**int** i);''
   * ''**native** **int** printChar(**char** c);''