[cpp] Align comments to common columns and fix some typography

Author: tkoeppe

source/preprocessor.tex

@@ -572,7 +572,7 @@
 #if VERSION == 1
     #define INCFILE  "vers1.h"
 #elif VERSION == 2
-    #define INCFILE  "vers2.h"   // and so on
+    #define INCFILE  "vers2.h"  // and so on
 #else
     #define INCFILE  "versN.h"
 #endif
@@ -1022,7 +1022,7 @@
 #define LOW         LOW ", world"
 
 debug(1, 2);
-fputs(str(strncmp("abc@\textbackslash@0d", "abc", '@\textbackslash@4')  // this goes away
+fputs(str(strncmp("abc@\textbackslash@0d", "abc", '@\textbackslash@4')        // this goes away
     == 0) str(: @\atsign\textbackslash@n), s);
 #include xstr(INCFILE(2).h)
 glue(HIGH, LOW);
@@ -1034,7 +1034,7 @@
 \begin{codeblock}
 printf("x" "1" "= %d, x" "2" "= %s", x1, x2);
 fputs("strncmp(@\textbackslash@"abc@\textbackslash\textbackslash@0d@\textbackslash@", @\textbackslash@"abc@\textbackslash@", '@\textbackslash\textbackslash@4') == 0" ": @\atsign\textbackslash@n", s);
-#include "vers2.h"    @\textit{(after macro replacement, before file access)}@
+#include "vers2.h"      @\textrm{(\textit{after macro replacement, before file access})}@
 "hello";
 "hello" ", world"
 \end{codeblock}
@@ -1044,7 +1044,7 @@
 \begin{codeblock}
 printf("x1= %d, x2= %s", x1, x2);
 fputs("strncmp(@\textbackslash@"abc@\textbackslash\textbackslash@0d@\textbackslash@", @\textbackslash@"abc@\textbackslash@", '@\textbackslash\textbackslash@4') == 0: @\atsign\textbackslash@n", s);
-#include "vers2.h"    @\textit{(after macro replacement, before file access)}@
+#include "vers2.h"      @\textrm{(\textit{after macro replacement, before file access})}@
 "hello";
 "hello, world"
 \end{codeblock}
@@ -1091,10 +1091,10 @@
 But the following redefinitions are invalid:
 
 \begin{codeblock}
-#define OBJ_LIKE    (0)      // different token sequence
-#define OBJ_LIKE    (1 - 1)  // different white space
-#define FUNC_LIKE(b) ( a )   // different parameter usage
-#define FUNC_LIKE(b) ( b )   // different parameter spelling
+#define OBJ_LIKE    (0)         // different token sequence
+#define OBJ_LIKE    (1 - 1)     // different white space
+#define FUNC_LIKE(b) ( a )      // different parameter usage
+#define FUNC_LIKE(b) ( b )      // different parameter spelling
 \end{codeblock}
 \end{example}