usr_{41,51,52}.txt: Update Vim 8.2.5048

Author: tsuyoshicho

en/usr_41.txt

@@ -1,4 +1,4 @@
-*usr_41.txt*	For Vim version 8.2.  Last change: 2022 May 13
+*usr_41.txt*	For Vim version 8.2.  Last change: 2022 May 21
 
 		     VIM USER MANUAL - by Bram Moolenaar
 
@@ -835,6 +835,7 @@ Cursor and mark position:		*cursor-functions* *mark-functions*
 	screencol()		get screen column of the cursor
 	screenrow()		get screen row of the cursor
 	screenpos()		screen row and col of a text character
+	virtcol2col()		byte index of a text character on screen
 	getcurpos()		get position of the cursor
 	getpos()		get position of cursor, mark, etc.
 	setpos()		set position of cursor, mark, etc.
@@ -925,6 +926,11 @@ Date and Time:				*date-functions* *time-functions*
 	reltimestr()		convert reltime() result to a string
 	reltimefloat()		convert reltime() result to a Float
 
+Autocmds:					*autocmd-functions*
+	autocmd_add()		add a list of autocmds and groups
+	autocmd_delete()	delete a list of autocmds and groups
+	autocmd_get()		return a list of autocmds
+
 			*buffer-functions* *window-functions* *arg-functions*
 Buffers, windows and the argument list:
 	argc()			number of entries in the argument list
@@ -1918,6 +1924,8 @@ are script-local.
 If you split your plugin into parts, you can use `import` and `export` to
 share items between those parts.  See `:export` for the details.
 
+More information about writing plugins is in |usr_51.txt|.
+
 ==============================================================================
 
 Next chapter: |usr_42.txt|  Add new menus

en/usr_51.txt

@@ -1,4 +1,4 @@
-*usr_51.txt*	For Vim version 8.2.  Last change: 2022 May 13
+*usr_51.txt*	For Vim version 8.2.  Last change: 2022 May 14
 
 		     VIM USER MANUAL - by Bram Moolenaar
 
@@ -197,8 +197,8 @@ would need to prefix the name with "s:".
 We will define a function that adds a new typing correction: >
 
  30	def Add(from: string, correct: bool)
- 31	  var to = input("type the correction for " .. from .. ": ")
- 32	  exe ":iabbrev " .. from .. " " .. to
+ 31	  var to = input($"type the correction for {from}: ")
+ 32	  exe $":iabbrev {from} {to}"
  ..
  36	enddef
 

en/usr_52.txt

@@ -1,4 +1,4 @@
-*usr_52.txt*	For Vim version 8.2.  Last change: 2022 May 13
+*usr_52.txt*	For Vim version 8.2.  Last change: 2022 May 21
 
 		     VIM USER MANUAL - by Bram Moolenaar
 
@@ -110,35 +110,36 @@ Although it's shorter to do: >
 ==============================================================================
 *52.3*	Functions and types
 
-Legacy Vim script does have type checking, but this happens at runtime, when
-the code is executed.  And it's permissive, often a computation gives an
-unexpected value instead of reporting an error.  Thus you can define a
-function and think it's fine, but see a problem only later when it is called: >
-	let s:collected = ''
-	func ExtendAndReturn(add)
-	   let s:collected += a:add
-	   return s:collected
+Legacy Vim script only checks types at runtime, when the code is executed.
+And it's permissive, often a computation gives an unexpected value instead of
+reporting an error.  Thus you can define a function and think it's fine, but
+notice a problem only later when the function is called: >
+	func Concatenate(base, add)
+	   return a:base + a:add
 	endfunc
 
 Can you spot the error?  Try this: >
-	echo ExtendAndReturn('text')
-And you'll see zero.  Why?  Because in legacy Vim script "+=" will convert the
-arguments to numbers, and any string without a number results in zero!
-
-With `:def` the type checking happens when compiling the function.  For that
-you need to specify the argument types and the return type.  Also notice that
-the argument is used without the "a:" prefix: >
-	let s:collected = ''
-	def ExtendAndReturn(add: string): string
-	   s:collected += add
-	   return s:collected
+	echo Concatenate('base', 'text')
+And you'll see zero.  Why?  Because in legacy Vim script "+" will convert the
+arguments to numbers, and any string without a number results in zero!  That's
+not what you expected.
+
+With `:def` the type checking happens when compiling the function.  You need
+to specify the argument types and the return type to make that possible.  Also
+notice that the argument names are used without the "a:" prefix: >
+	def Concatenate(base: string, add: string): string
+	   return base + add
 	enddef
-	defcompile
+	defcompile Concatenate
 
 Here we use `:defcompile` to do the compilation right away, without it the
-compilation would happen when the function is called.  Vim will tell you what
-you did wrong: >
-	E1013: type mismatch, expected number but got string
+compilation would happen when the function is first called.  Vim will tell you
+what you did wrong: >
+	E1051: Wrong argument type for +
+
+Side note: here the context is legacy script.  When using Vim9 script you
+would put `:defcompile` at the end of the script to check for errors in all
+the functions defined in it.
 
 Vim9 script is strict, it uses the "+" operator only for numbers and floats.
 For string concatenation ".." must be used.  This avoids mistakes and avoids