[SOLVED] Insert comment // when conditions do not match

Issue

How to get the desired output? For a text file, when one of these conditions are met:

- the first field of a line has the string "type" or "const" (all lowercase)
- the line has "(" and ")" and do not have the string "ch" followed by a number (e.g. "ch6")
- a multiline which start with "{" somewhere of a line and end with "}" as the first character of a line
- the line start with comment "//"
- empty lines or lines of all white space
- a line has "{" and "}" 

then print (as usual),
else insert comment "//" in the beginning of line and print

e.g. input:

TypeScript ch6 (2/3) Advanced Function Types
 Types TypeScript  
  Totality TSC Flag: noImplicitReturns Advanced Object Types
   The keyof operator TSC Flag: keyofStringsOnly The Record Type Mapped Types Built-in mapped types 
type Weekday = 'Mon' | 'Tue' | 'Wed'|'Thu'|'Fri'

type Day = Weekday | 'Sat' | 'Sun'
// Error: Function lacks ending return statement and return type does not include 'undefined'.
function getNextDay(w: Weekday): Day {
  switch(w) {
    case 'Mon': return 'Tue'
  }
}
{  }
{
}
{
  {
    test
  }
}
const i = 1
 TSC Flag: noImplicitReturns tsconfig"noImplicitReturns": true // Error: Not all code paths return a value.
function isBig(n: number) {
  if (n >= 100) {
    return true
  }
}
 Advanced Object Types Type Operators for Object Types 
 Companion Object Pattern
type APIResponse = {
  user: {
    userId: string,
    friendList: {
      count: number,
      friends: {
        firstName: string,
        lastName: string
      }[]
    }
  }
}
function getAPIResponse(): Promise<APIResponse> {
  // ...
}
const response = await getAPIResponse()
renderFriendList(response.user.friendList)
 friendListtypehint any FriendList

output:

//TypeScript ch6 (2/3) Advanced Function Types
// Types TypeScript  
//  Totality TSC Flag: noImplicitReturns Advanced Object Types
//   The keyof operator TSC Flag: keyofStringsOnly The Record Type Mapped Types Built-in mapped types 
type Weekday = 'Mon' | 'Tue' | 'Wed'|'Thu'|'Fri'

type Day = Weekday | 'Sat' | 'Sun'
// Error: Function lacks ending return statement and return type does not include 'undefined'.
function getNextDay(w: Weekday): Day {
  switch(w) {
    case 'Mon': return 'Tue'
  }
}
{  }
{
}
{
  {
    test
  }
}
const i = 1
// TSC Flag: noImplicitReturns tsconfig"noImplicitReturns": true // Error: Not all code paths return a value.
function isBig(n: number) {
  if (n >= 100) {
    return true
  }
}
// Advanced Object Types Type Operators for Object Types 
// Companion Object Pattern
type APIResponse = {
  user: {
    userId: string,
    friendList: {
      count: number,
      friends: {
        firstName: string,
        lastName: string
      }[]
    }
  }
}
function getAPIResponse(): Promise<APIResponse> {
  // ...
}
const response = await getAPIResponse()
renderFriendList(response.user.friendList)
// friendListtypehint any FriendList

I tried this script, which did not handle properly 'a multiline which start with "{" somewhere of a line and end with "}" as the first character of a line':

awk '{
  if ($1 ~ /type/ || $1 ~ /const/ || $0 ~ /\(.*)/ || $0 ~ /{.*}/ || $0 ~ /\/\//)
    print $0;
  else
    if ($0 !~ /}/)
      print "//", $0;
    else 
      print $0;
}' input

Solution

Using any awk:

$ cat tst.awk
{
    comment = 0
    if ( inBlock ) {
        if ( /^}/ ) {
            inBlock = 0
        }
    }
    else if ( /\{$/ ) {
        inBlock = 1
    }
    else if ( NF && !(                           \
                ( $1 ~ /^(type|const|\/\/)/ ) || \
                ( /\(.*)/ && !/ch[0-9]/ ) ||     \
                ( /\{.*}/ )                      \
            ) ) {
        comment = 1
    }
}
comment {
    $0 = "//" $0
}
{ print }

$ awk -f tst.awk file
//TypeScript ch6 (2/3) Advanced Function Types
// Types TypeScript
//  Totality TSC Flag: noImplicitReturns Advanced Object Types
//   The keyof operator TSC Flag: keyofStringsOnly The Record Type Mapped Types Built-in mapped types
type Weekday = 'Mon' | 'Tue' | 'Wed'|'Thu'|'Fri'

type Day = Weekday | 'Sat' | 'Sun'
// Error: Function lacks ending return statement and return type does not include 'undefined'.
function getNextDay(w: Weekday): Day {
  switch(w) {
    case 'Mon': return 'Tue'
  }
}
{  }
{
}
{
  {
    test
  }
}
const i = 1
// TSC Flag: noImplicitReturns tsconfig"noImplicitReturns": true // Error: Not all code paths return a value.
function isBig(n: number) {
  if (n >= 100) {
    return true
  }
}
// Advanced Object Types Type Operators for Object Types
// Companion Object Pattern
type APIResponse = {
  user: {
    userId: string,
    friendList: {
      count: number,
      friends: {
        firstName: string,
        lastName: string
      }[]
    }
  }
}
function getAPIResponse(): Promise<APIResponse> {
  // ...
}
const response = await getAPIResponse()
renderFriendList(response.user.friendList)
// friendListtypehint any FriendList

Answered By - Ed Morton

Answer Checked By - Timothy Miller (WPSolving Admin)