Improve some comments in scanner files

Reviewed-by: John Naylor 
Discussion: https://www.postgresql.org/message-id/flat/b239564c-cad0-b23e-c57e-166d883cb97d@enterprisedb.com

diff --git a/src/backend/parser/scan.l b/src/backend/parser/scan.l
index 6e6824faebd28ad995c42466e52385741befd2ac..76fd6996eda72e85503cd5aa60d907b0af32ae5a 100644 (file)
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -174,7 +174,7 @@ extern void core_yyset_column(int column_no, yyscan_t yyscanner);
  *   bit string literal
  *   extended C-style comments
  *   delimited identifiers (double-quoted identifiers)
- *   hexadecimal numeric string
+ *   hexadecimal byte string
  *   standard quoted strings
  *   quote stop (detect continued strings)
  *   extended quoted strings (support backslash escape sequences)
@@ -262,7 +262,7 @@ quotecontinuefail   {whitespace}*"-"?
 xbstart            [bB]{quote}
 xbinside       [^']*
 
-/* Hexadecimal number */
+/* Hexadecimal byte string */
 xhstart            [xX]{quote}
 xhinside       [^']*
 
@@ -341,7 +341,6 @@ xcstart         \/\*{op_chars}*
 xcstop         \*+\/
 xcinside       [^*/]+
 
-digit          [0-9]
 ident_start        [A-Za-z\200-\377_]
 ident_cont     [A-Za-z\200-\377_0-9\$]
 
@@ -380,15 +379,18 @@ self          [,()\[\].;\:\+\-\*\/\%\^\<\>\=]
 op_chars       [\~\!\@\#\^\&\|\`\?\+\-\*\/\%\<\>\=]
 operator       {op_chars}+
 
-/* we no longer allow unary minus in numbers.
- * instead we pass it separately to parser. there it gets
- * coerced via doNegate() -- Leon aug 20 1999
+/*
+ * Numbers
+ *
+ * Unary minus is not part of a number here.  Instead we pass it separately to
+ * the parser, and there it gets coerced via doNegate().
  *
  * {decimalfail} is used because we would like "1..10" to lex as 1, dot_dot, 10.
  *
  * {realfail1} and {realfail2} are added to prevent the need for scanner
  * backup when the {real} rule fails to match completely.
  */
+digit          [0-9]
 
 integer            {digit}+
 decimal            (({digit}*\.{digit}+)|({digit}+\.{digit}*))

diff --git a/src/fe_utils/psqlscan.l b/src/fe_utils/psqlscan.l
index 0fab48a38253a060debf282bd83df8e8865589ad..b0fd4394ec6bb0cdbf46dc5f4523279c9c97aa12 100644 (file)
--- a/src/fe_utils/psqlscan.l
+++ b/src/fe_utils/psqlscan.l
@@ -112,7 +112,7 @@ extern void psql_yyset_column(int column_no, yyscan_t yyscanner);
  *   bit string literal
  *   extended C-style comments
  *   delimited identifiers (double-quoted identifiers)
- *   hexadecimal numeric string
+ *   hexadecimal byte string
  *   standard quoted strings
  *   quote stop (detect continued strings)
  *   extended quoted strings (support backslash escape sequences)
@@ -200,7 +200,7 @@ quotecontinuefail   {whitespace}*"-"?
 xbstart            [bB]{quote}
 xbinside       [^']*
 
-/* Hexadecimal number */
+/* Hexadecimal byte string */
 xhstart            [xX]{quote}
 xhinside       [^']*
 
@@ -279,7 +279,6 @@ xcstart         \/\*{op_chars}*
 xcstop         \*+\/
 xcinside       [^*/]+
 
-digit          [0-9]
 ident_start        [A-Za-z\200-\377_]
 ident_cont     [A-Za-z\200-\377_0-9\$]
 
@@ -318,15 +317,18 @@ self          [,()\[\].;\:\+\-\*\/\%\^\<\>\=]
 op_chars       [\~\!\@\#\^\&\|\`\?\+\-\*\/\%\<\>\=]
 operator       {op_chars}+
 
-/* we no longer allow unary minus in numbers.
- * instead we pass it separately to parser. there it gets
- * coerced via doNegate() -- Leon aug 20 1999
+/*
+ * Numbers
+ *
+ * Unary minus is not part of a number here.  Instead we pass it separately to
+ * the parser, and there it gets coerced via doNegate().
  *
  * {decimalfail} is used because we would like "1..10" to lex as 1, dot_dot, 10.
  *
  * {realfail1} and {realfail2} are added to prevent the need for scanner
  * backup when the {real} rule fails to match completely.
  */
+digit          [0-9]
 
 integer            {digit}+
 decimal            (({digit}*\.{digit}+)|({digit}+\.{digit}*))

diff --git a/src/interfaces/ecpg/preproc/pgc.l b/src/interfaces/ecpg/preproc/pgc.l
index 7a0356638d70e9b8a05314eef459c2443a01d588..a2f8c7f3d88e0be1c51ef911429b64a165f3faab 100644 (file)
--- a/src/interfaces/ecpg/preproc/pgc.l
+++ b/src/interfaces/ecpg/preproc/pgc.l
@@ -130,7 +130,7 @@ static struct _if_value
  *   extended C-style comments
  *   delimited identifiers (double-quoted identifiers)
  *   double-quoted strings in C
- *   hexadecimal numeric string
+ *   hexadecimal byte string
  *   national character quoted strings
  *   standard quoted strings
  *   quote stop (detect continued strings)
@@ -223,7 +223,7 @@ quotecontinuefail   {whitespace}*"-"?
 xbstart            [bB]{quote}
 xbinside       [^']*
 
-/* Hexadecimal number */
+/* Hexadecimal byte string */
 xhstart            [xX]{quote}
 xhinside       [^']*
 
@@ -305,7 +305,6 @@ xcstart         \/\*{op_chars}*
 xcstop         \*+\/
 xcinside       [^*/]+
 
-digit          [0-9]
 ident_start        [A-Za-z\200-\377_]
 ident_cont     [A-Za-z\200-\377_0-9\$]
 
@@ -346,15 +345,18 @@ self          [,()\[\].;\:\+\-\*\/\%\^\<\>\=]
 op_chars       [\~\!\@\#\^\&\|\`\?\+\-\*\/\%\<\>\=]
 operator       {op_chars}+
 
-/* we no longer allow unary minus in numbers.
- * instead we pass it separately to parser. there it gets
- * coerced via doNegate() -- Leon aug 20 1999
+/*
+ * Numbers
+ *
+ * Unary minus is not part of a number here.  Instead we pass it separately to
+ * the parser, and there it gets coerced via doNegate().
  *
  * {decimalfail} is used because we would like "1..10" to lex as 1, dot_dot, 10.
  *
  * {realfail1} and {realfail2} are added to prevent the need for scanner
  * backup when the {real} rule fails to match completely.
  */
+digit          [0-9]
 
 integer            {digit}+
 decimal            (({digit}*\.{digit}+)|({digit}+\.{digit}*))
@@ -603,7 +605,7 @@ cppline         {space}*#([^i][A-Za-z]*|{if}|{ifdef}|{ifndef}|{import})((\/\*[^*/]*\*+
                            return BCONST;
                        case xh:
                            if (literalbuf[strspn(literalbuf, "0123456789abcdefABCDEF")] != '\0')
-                               mmerror(PARSE_ERROR, ET_ERROR, "invalid hex string literal");
+                               mmerror(PARSE_ERROR, ET_ERROR, "invalid hexadecimal string literal");
                            base_yylval.str = psprintf("x'%s'", literalbuf);
                            return XCONST;
                        case xq: