From 1546ef34404baa8d01144be811f03651b170d4a4 Mon Sep 17 00:00:00 2001
From: Godara-aman <amangodara891@gmail.com>
Date: Sun, 14 Mar 2021 17:48:42 +0530
Subject: [PATCH 01/12] added interface for to_lower, to_upper, to_title,
 reverse functions

---
 src/stdlib_ascii.f90       | 30 ++++++++++++++++
 src/stdlib_string_type.f90 | 70 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 98 insertions(+), 2 deletions(-)

diff --git a/src/stdlib_ascii.f90 b/src/stdlib_ascii.f90
index a9111888a..1dc0cdc4f 100644
--- a/src/stdlib_ascii.f90
+++ b/src/stdlib_ascii.f90
@@ -64,6 +64,36 @@ module stdlib_ascii
     character(len=*), public, parameter :: lowercase = letters(27:) !! a .. z
     character(len=*), public, parameter :: whitespace = " "//TAB//VT//CR//LF//FF !! ASCII _whitespace
 
+
+    !> Convert character variable to lower case
+    !>
+    !> This method is pure and returns a character sequence
+    interface to_lower
+        module procedure :: to_lower
+    end interface to_lower
+
+    !> Convert character variable to upper case
+    !>
+    !> This method is pure and returns a character sequence
+    interface to_upper
+        module procedure :: to_upper
+    end interface to_upper
+
+    !> Convert character variable to title case
+    !>
+    !> This method is pure and returns a character sequence
+    interface to_title
+        module procedure :: to_title
+    end interface to_title
+
+    !> Reverse the character order in the input character variable
+    !>
+    !> This method is pure and returns a character sequence
+    interface reverse
+        module procedure :: reverse
+    end interface reverse
+    
+
 contains
 
     !> Checks whether `c` is an ASCII letter (A .. Z, a .. z).
diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index ebc5f1485..8eabc6b69 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -12,11 +12,13 @@
 !>
 !> The specification of this module is available [here](../page/specs/stdlib_string_type.html).
 module stdlib_string_type
+    use stdlib_ascii, only: to_lower, to_upper, to_title, reverse
+
     implicit none
     private
-
+    
     public :: string_type
-    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, adjustl
+    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, adjustl, to_lower, to_upper, to_title, reverse
     public :: lgt, lge, llt, lle, char, ichar, iachar
     public :: assignment(=)
     public :: operator(>), operator(>=), operator(<), operator(<=)
@@ -89,6 +91,34 @@ module stdlib_string_type
         module procedure :: repeat_string
     end interface repeat
 
+    !> 
+    !>
+    !>
+    interface to_lower
+        module procedure :: to_lower_string
+    end interface to_lower
+
+    !>
+    !>
+    !>
+    interface to_upper
+        module procedure :: to_upper_string
+    end interface to_upper
+
+    !>
+    !>
+    !>
+    interface to_title
+        module procedure :: to_title_string
+    end interface to_title
+
+    !>
+    !>
+    !>
+    interface reverse
+        module procedure :: reverse_string
+    end interface reverse
+
     !> Return the character sequence represented by the string.
     !>
     !> This method is elemental and returns a scalar character value.
@@ -447,6 +477,42 @@ elemental function repeat_string(string, ncopies) result(repeated_string)
     end function repeat_string
 
 
+    elemental function to_lower_string(string) result(lowered_string)
+        type(string_type), intent(in) :: string
+        type(string_type) :: lowered_string
+
+        lowered_string%raw = to_lower(string%raw)
+
+    end function to_lower_string
+
+
+    elemental function to_upper_string(string) result(uppered_string)
+        type(string_type), intent(in) :: string
+        type(string_type) :: uppered_string
+
+        uppered_string%raw = to_upper(string%raw)
+
+    end function to_upper_string
+
+
+    elemental function to_title_string(string) result(titled_string)
+        type(string_type), intent(in) :: string
+        type(string_type) :: titled_string
+
+        titled_string%raw = to_title(string%raw)
+
+    end function to_title_string
+
+
+    elemental function reverse_string(string) result(reversed_string)
+        type(string_type), intent(in) :: string
+        type(string_type) :: reversed_string
+
+        reversed_string%raw = reverse(string%raw)
+
+    end function reverse_string
+
+
     !> Position of a sequence of character within a character sequence.
     !> In this version both character sequences are represented by a string.
     elemental function index_string_string(string, substring, back) result(pos)

From 30ea5af56e6b11de940bf5595273006643eedbf4 Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Mon, 15 Mar 2021 11:51:03 +0530
Subject: [PATCH 02/12] added better comments to the stdlib_ascii.f90

---
 src/stdlib_ascii.f90 | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/stdlib_ascii.f90 b/src/stdlib_ascii.f90
index 1dc0cdc4f..d797d33b1 100644
--- a/src/stdlib_ascii.f90
+++ b/src/stdlib_ascii.f90
@@ -65,29 +65,29 @@ module stdlib_ascii
     character(len=*), public, parameter :: whitespace = " "//TAB//VT//CR//LF//FF !! ASCII _whitespace
 
 
-    !> Convert character variable to lower case
-    !>
+    !> Returns a new character sequence which is the lower case 
+    !> version of the input character sequence
     !> This method is pure and returns a character sequence
     interface to_lower
         module procedure :: to_lower
     end interface to_lower
 
-    !> Convert character variable to upper case
-    !>
+    !> Returns a new character sequence which is the upper case
+    !> version of the input character sequence
     !> This method is pure and returns a character sequence
     interface to_upper
         module procedure :: to_upper
     end interface to_upper
 
-    !> Convert character variable to title case
-    !>
+    !> Returns a new character sequence which is the titled
+    !> version of the input character sequence
     !> This method is pure and returns a character sequence
     interface to_title
         module procedure :: to_title
     end interface to_title
 
-    !> Reverse the character order in the input character variable
-    !>
+    !> Returns a new character sequence which is the reversed
+    !> version of the input charater sequence
     !> This method is pure and returns a character sequence
     interface reverse
         module procedure :: reverse

From 4d3cd0d5569135dc4e8b3e3ce1c0876df486268b Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Mon, 15 Mar 2021 12:05:31 +0530
Subject: [PATCH 03/12] added comments to stdlib_string_type.f90.   function is
 elemental or pure (query)??

---
 src/stdlib_string_type.f90 | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index 8eabc6b69..5e842a285 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -91,30 +91,30 @@ module stdlib_string_type
         module procedure :: repeat_string
     end interface repeat
 
-    !> 
-    !>
+    !> Convert the character sequence hold by the input string to lower case
     !>
+    !> Elemental or pure ???? Does not return anything
     interface to_lower
         module procedure :: to_lower_string
     end interface to_lower
 
+    !> Convert the character sequence hold by the input string to upper case
     !>
-    !>
-    !>
+    !> Elemental or pure ???? Does not return anything
     interface to_upper
         module procedure :: to_upper_string
     end interface to_upper
 
+    !> Convert the character sequence hold by the input string to title case
     !>
-    !>
-    !>
+    !> Elemental or pure ???? Does not return anything
     interface to_title
         module procedure :: to_title_string
     end interface to_title
 
-    !>
-    !>
-    !>
+    !> Reverse the character sequence hold by the input string
+    !> 
+    !> Elemental or pure ???? Does not return anything
     interface reverse
         module procedure :: reverse_string
     end interface reverse
@@ -477,6 +477,7 @@ elemental function repeat_string(string, ncopies) result(repeated_string)
     end function repeat_string
 
 
+    !> Convert the character sequence hold by the input string to lower case
     elemental function to_lower_string(string) result(lowered_string)
         type(string_type), intent(in) :: string
         type(string_type) :: lowered_string
@@ -486,6 +487,7 @@ elemental function to_lower_string(string) result(lowered_string)
     end function to_lower_string
 
 
+    !> Convert the character sequence hold by the input string to upper case
     elemental function to_upper_string(string) result(uppered_string)
         type(string_type), intent(in) :: string
         type(string_type) :: uppered_string
@@ -495,6 +497,7 @@ elemental function to_upper_string(string) result(uppered_string)
     end function to_upper_string
 
 
+    !> Convert the character sequence hold by the input string to title case
     elemental function to_title_string(string) result(titled_string)
         type(string_type), intent(in) :: string
         type(string_type) :: titled_string
@@ -504,6 +507,7 @@ elemental function to_title_string(string) result(titled_string)
     end function to_title_string
 
 
+    !> Reverse the character sequence hold by the input string
     elemental function reverse_string(string) result(reversed_string)
         type(string_type), intent(in) :: string
         type(string_type) :: reversed_string

From 6dde4d6414f0ee7ea7bc61a65c9292c8f4da7fa2 Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Mon, 15 Mar 2021 12:09:07 +0530
Subject: [PATCH 04/12] improved line spacing; nothing special in this commit

---
 src/stdlib_string_type.f90 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index 5e842a285..a496cf85e 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -16,7 +16,7 @@ module stdlib_string_type
 
     implicit none
     private
-    
+
     public :: string_type
     public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, adjustl, to_lower, to_upper, to_title, reverse
     public :: lgt, lge, llt, lle, char, ichar, iachar

From 2dd965d6d266d1c78ae2b5a9e25ed225bca0122e Mon Sep 17 00:00:00 2001
From: Aman Godara <34789087+Aman-Godara@users.noreply.github.com>
Date: Mon, 15 Mar 2021 17:18:24 +0530
Subject: [PATCH 05/12] cleaning namespace and using the maybe

Note: here how using maybe(string) automatically access the string%raw.
maybe is used for safe memory access.

Co-authored-by: Sebastian Ehlert <28669218+awvwgk@users.noreply.github.com>
---
 src/stdlib_string_type.f90 | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index a496cf85e..067526987 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -12,7 +12,7 @@
 !>
 !> The specification of this module is available [here](../page/specs/stdlib_string_type.html).
 module stdlib_string_type
-    use stdlib_ascii, only: to_lower, to_upper, to_title, reverse
+    use stdlib_ascii, only: to_lower_ => to_lower, to_upper_ => to_upper, to_title_ => to_title, reverse_ => reverse
 
     implicit none
     private
@@ -482,7 +482,7 @@ elemental function to_lower_string(string) result(lowered_string)
         type(string_type), intent(in) :: string
         type(string_type) :: lowered_string
 
-        lowered_string%raw = to_lower(string%raw)
+        lowered_string%raw = to_lower_(maybe(string))
 
     end function to_lower_string
 
@@ -492,7 +492,7 @@ elemental function to_upper_string(string) result(uppered_string)
         type(string_type), intent(in) :: string
         type(string_type) :: uppered_string
 
-        uppered_string%raw = to_upper(string%raw)
+        uppered_string%raw = to_upper_(maybe(string))
 
     end function to_upper_string
 
@@ -502,7 +502,7 @@ elemental function to_title_string(string) result(titled_string)
         type(string_type), intent(in) :: string
         type(string_type) :: titled_string
 
-        titled_string%raw = to_title(string%raw)
+        titled_string%raw = to_title_(maybe(string))
 
     end function to_title_string
 
@@ -512,7 +512,7 @@ elemental function reverse_string(string) result(reversed_string)
         type(string_type), intent(in) :: string
         type(string_type) :: reversed_string
 
-        reversed_string%raw = reverse(string%raw)
+        reversed_string%raw = reverse_(maybe(string))
 
     end function reverse_string
 

From 692d13b64416803ffdc7e790375e62c0f861971f Mon Sep 17 00:00:00 2001
From: milancurcic <caomaco@gmail.com>
Date: Mon, 15 Mar 2021 13:11:37 -0400
Subject: [PATCH 06/12] stay within 80 characters line length

---
 src/stdlib_string_type.f90 | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index 067526987..106f370ba 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -12,13 +12,15 @@
 !>
 !> The specification of this module is available [here](../page/specs/stdlib_string_type.html).
 module stdlib_string_type
-    use stdlib_ascii, only: to_lower_ => to_lower, to_upper_ => to_upper, to_title_ => to_title, reverse_ => reverse
+    use stdlib_ascii, only: to_lower_ => to_lower, to_upper_ => to_upper, &
+                            to_title_ => to_title, reverse_ => reverse
 
     implicit none
     private
 
     public :: string_type
-    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, adjustl, to_lower, to_upper, to_title, reverse
+    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, &
+              adjustl, to_lower, to_upper, to_title, reverse
     public :: lgt, lge, llt, lle, char, ichar, iachar
     public :: assignment(=)
     public :: operator(>), operator(>=), operator(<), operator(<=)

From fbde735625a6c556a440dc90f358606d15463390 Mon Sep 17 00:00:00 2001
From: milancurcic <caomaco@gmail.com>
Date: Mon, 15 Mar 2021 13:14:23 -0400
Subject: [PATCH 07/12] fix result variable names

---
 src/stdlib_string_type.f90 | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index 106f370ba..f98376e07 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -480,31 +480,31 @@ end function repeat_string
 
 
     !> Convert the character sequence hold by the input string to lower case
-    elemental function to_lower_string(string) result(lowered_string)
+    elemental function to_lower_string(string) result(lowercase_string)
         type(string_type), intent(in) :: string
-        type(string_type) :: lowered_string
+        type(string_type) :: lowercase_string
 
-        lowered_string%raw = to_lower_(maybe(string))
+        lowercase_string%raw = to_lower_(maybe(string))
 
     end function to_lower_string
 
 
     !> Convert the character sequence hold by the input string to upper case
-    elemental function to_upper_string(string) result(uppered_string)
+    elemental function to_upper_string(string) result(uppercase_string)
         type(string_type), intent(in) :: string
-        type(string_type) :: uppered_string
+        type(string_type) :: uppercase_string
 
-        uppered_string%raw = to_upper_(maybe(string))
+        uppercase_string%raw = to_upper_(maybe(string))
 
     end function to_upper_string
 
 
     !> Convert the character sequence hold by the input string to title case
-    elemental function to_title_string(string) result(titled_string)
+    elemental function to_title_string(string) result(titlecase_string)
         type(string_type), intent(in) :: string
-        type(string_type) :: titled_string
+        type(string_type) :: titlecase_string
 
-        titled_string%raw = to_title_(maybe(string))
+        titlecase_string%raw = to_title_(maybe(string))
 
     end function to_title_string
 

From 9f82abbf5098fc9fa31af8e1efee5b813683a1b6 Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Thu, 18 Mar 2021 22:59:47 +0530
Subject: [PATCH 08/12] added dependency of modules in Makefile.manual, updated
 comments, fixed typo in README.md

---
 README.md                  |  2 +-
 src/Makefile.manual        |  1 +
 src/stdlib_string_type.f90 | 12 ++++++++----
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index d82cf2897..5873bbd57 100644
--- a/README.md
+++ b/README.md
@@ -138,7 +138,7 @@ To test your build, run the test suite after the build has finished with
 cmake --build build --target test
 ```
 
-Please report failing tests on our [issue tracker](https://github.com/fortran-lang/stdlib/issues/new/choose) including details on the compiler used, the operating system and platform architecture.
+Please report failing tests on our [issue tracker](https://github.com/fortran-lang/stdlib/issues/new/choose) including details of the compiler used, the operating system and platform architecture.
 
 To install the project to the declared prefix run
 
diff --git a/src/Makefile.manual b/src/Makefile.manual
index 804b04272..b59340b8c 100644
--- a/src/Makefile.manual
+++ b/src/Makefile.manual
@@ -109,3 +109,4 @@ stdlib_stats_var.o: \
 stdlib_stats_distribution_PRNG.o: \
         stdlib_kinds.o \
 	stdlib_error.o
+stdlib_string_type.o: stdlib_ascii.o
\ No newline at end of file
diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index f98376e07..ba1e7d523 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -95,28 +95,32 @@ module stdlib_string_type
 
     !> Convert the character sequence hold by the input string to lower case
     !>
-    !> Elemental or pure ???? Does not return anything
+    !> This method is Elemental and returns a new string_type instance which holds lowercase
+    !> version of the character sequence hold by the input string
     interface to_lower
         module procedure :: to_lower_string
     end interface to_lower
 
     !> Convert the character sequence hold by the input string to upper case
     !>
-    !> Elemental or pure ???? Does not return anything
+    !> This method is Elemental and returns a new string_type instance which holds uppercase
+    !> version of the character sequence hold by the input string
     interface to_upper
         module procedure :: to_upper_string
     end interface to_upper
 
     !> Convert the character sequence hold by the input string to title case
     !>
-    !> Elemental or pure ???? Does not return anything
+    !> This method is Elemental and returns a new string_type instance which holds titlecase
+    !> version of the character sequence hold by the input string
     interface to_title
         module procedure :: to_title_string
     end interface to_title
 
     !> Reverse the character sequence hold by the input string
     !> 
-    !> Elemental or pure ???? Does not return anything
+    !> This method is Elemental and returns a new string_type instance which holds reversed
+    !> sequence of the character sequence hold by the input string
     interface reverse
         module procedure :: reverse_string
     end interface reverse

From f36f0c1ca89111d3726c9aa7d37e3630f910a57f Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Fri, 19 Mar 2021 01:16:21 +0530
Subject: [PATCH 09/12] adding unit tests for to_lower, to_upper, reverse,
 to_title functions of stdlib_string_type module

---
 src/tests/string/test_string_functions.f90 | 58 ++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 src/tests/string/test_string_functions.f90

diff --git a/src/tests/string/test_string_functions.f90 b/src/tests/string/test_string_functions.f90
new file mode 100644
index 000000000..7adeffa17
--- /dev/null
+++ b/src/tests/string/test_string_functions.f90
@@ -0,0 +1,58 @@
+! SPDX-Identifier: MIT
+module test_string_functions
+    use stdlib_error, only : check
+    use stdlib_string_type, only : string_type, assignment(=), operator(==), &
+                                    to_lower, to_upper, to_title, reverse
+    implicit none
+
+contains
+
+    subroutine test_to_lower_string
+        type(string_type) :: test_string, compare_string
+        test_string = "To_LoWEr !$%-az09AZ"
+        compare_string = "to_lower !$%-az09az"
+
+        call check(to_lower(test_string) == compare_string)
+
+    end subroutine test_to_lower_string
+
+    subroutine test_to_upper_string
+        type(string_type) :: test_string, compare_string
+        test_string = "To_UpPeR !$%-az09AZ"
+        compare_string = "TO_UPPER !$%-AZ09AZ"
+
+        call check(to_upper(test_string) == compare_string)
+
+    end subroutine test_to_upper_string
+
+    subroutine test_to_title_string
+        type(string_type) :: test_string, compare_string
+        test_string = "_#To tiTlE !$%-az09AZ"
+        compare_string = "_#To title !$%-a09az"
+
+        call check(to_title(test_string) == compare_string)
+
+    end subroutine test_to_title_string
+
+    subroutine test_reverse_string
+        type(string_type) :: test_string, compare_string
+        test_string = "_To ReVerSe !$%-az09AZ   "
+        compare_string = "   ZA90za-%$! eSreVeR oT_"
+
+        call check(reverse(test_string) == compare_string)
+
+    end subroutine test_reverse_string
+
+end module test_string_functions
+
+
+program tester
+    use test_string_functions
+    implicit none
+
+    call test_to_lower_string
+    call test_to_upper_string
+    call test_to_title_string
+    call test_reverse_string
+
+end program tester

From 006175d3f385c0d0d37be2ebe3d6258a27aa5d36 Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Fri, 19 Mar 2021 16:01:31 +0530
Subject: [PATCH 10/12] Documented the newly created functions in
 stdlib_string_type.md

---
 doc/specs/stdlib_string_type.md | 179 ++++++++++++++++++++++++++++++++
 src/stdlib_string_type.f90      |  24 ++---
 2 files changed, 191 insertions(+), 12 deletions(-)

diff --git a/doc/specs/stdlib_string_type.md b/doc/specs/stdlib_string_type.md
index adbf7483e..7a4472397 100644
--- a/doc/specs/stdlib_string_type.md
+++ b/doc/specs/stdlib_string_type.md
@@ -1041,6 +1041,185 @@ end program demo
 ```
 
 
+<!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
+### To\_lower function
+
+#### Description
+
+Returns a new string_type instance which holds the lowercase version of the character sequence hold by the input string.
+
+#### Syntax
+
+`lowercase_string = [[stdlib_string_type(module): to_lower(interface)]] (string)`
+
+#### Status
+
+Experimental
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`string`: Instance of `string_type`. This argument is `intent(in)`.
+
+#### Result Value
+
+The Result is a scalar `string_type` value.
+
+#### Example
+
+```fortran
+program demo
+  use stdlib_string_type
+  implicit none
+  type(string_type) :: string, lowercase_string
+
+  string = "Lowercase This String"
+  ! string <-- "Lowercase This String"
+
+  lowercase_string = to_lower(string)
+  ! string <-- "Lowercase This String"
+  ! lowercase_string <-- "lowercase this string"
+end program demo
+```
+
+
+<!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
+### To\_upper function
+
+#### Description
+
+Returns a new string_type instance which holds the uppercase version of the character sequence hold by the input string.
+
+#### Syntax
+
+`uppercase_string = [[stdlib_string_type(module): to_upper(interface)]] (string)`
+
+#### Status
+
+Experimental
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`string`: Instance of `string_type`. This argument is `intent(in)`.
+
+#### Result Value
+
+The Result is a scalar `string_type` value.
+
+#### Example
+
+```fortran
+program demo
+  use stdlib_string_type
+  implicit none
+  type(string_type) :: string, uppercase_string
+
+  string = "Uppercase This String"
+  ! string <-- "Uppercase This String"
+
+  uppercase_string = to_upper(string)
+  ! string <-- "Uppercase This String"
+  ! uppercase_string <-- "UPPERCASE THIS STRING"
+end program demo
+```
+
+
+<!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
+### To\_title function
+
+#### Description
+
+Returns a new string_type instance which holds the titlecase version of the character sequence hold by the input string.
+
+#### Syntax
+
+`titlecase_string = [[stdlib_string_type(module): to_title(interface)]] (string)`
+
+#### Status
+
+Experimental
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`string`: Instance of `string_type`. This argument is `intent(in)`.
+
+#### Result Value
+
+The Result is a scalar `string_type` value.
+
+#### Example
+
+```fortran
+program demo
+  use stdlib_string_type
+  implicit none
+  type(string_type) :: string, titlecase_string
+
+  string = "Titlecase This String"
+  ! string <-- "Titlecase This String"
+
+  titlecase_string = to_title(string)
+  ! string <-- "Titlecase This String"
+  ! titlecase_string <-- "Titlecase this string"
+end program demo
+```
+
+<!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
+### Reverse function
+
+#### Description
+
+Returns a new string_type instance which holds the reversed version of the character sequence hold by the input string.
+
+#### Syntax
+
+`reverse_string = [[stdlib_string_type(module): reverse(interface)]] (string)`
+
+#### Status
+
+Experimental
+
+#### Class
+
+Elemental function.
+
+#### Argument
+
+`string`: Instance of `string_type`. This argument is `intent(in)`.
+
+#### Result Value
+
+The Result is a scalar `string_type` value.
+
+#### Example
+
+```fortran
+program demo
+  use stdlib_string_type
+  implicit none
+  type(string_type) :: string, reverse_string
+  
+  string = "Reverse This String"
+  ! string <-- "Reverse This String"
+
+  reverse_string = reverse(string)
+  ! string <-- "Reverse This String"
+  ! reverse_string <-- "gnirtS sihT esreveR"
+end program demo
+```
+
+
 <!-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -->
 ### Comparison operator greater
 
diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index ba1e7d523..3a30513ef 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -93,34 +93,34 @@ module stdlib_string_type
         module procedure :: repeat_string
     end interface repeat
 
-    !> Convert the character sequence hold by the input string to lower case
+    !> Returns the lowercase version of the character sequence hold by the input string
     !>
-    !> This method is Elemental and returns a new string_type instance which holds lowercase
-    !> version of the character sequence hold by the input string
+    !> This method is Elemental and returns a new string_type instance which holds this
+    !> lowercase character sequence
     interface to_lower
         module procedure :: to_lower_string
     end interface to_lower
 
-    !> Convert the character sequence hold by the input string to upper case
+    !> Returns the uppercase version of the character sequence hold by the input string
     !>
-    !> This method is Elemental and returns a new string_type instance which holds uppercase
-    !> version of the character sequence hold by the input string
+    !> This method is Elemental and returns a new string_type instance which holds this
+    !> uppercase character sequence
     interface to_upper
         module procedure :: to_upper_string
     end interface to_upper
 
-    !> Convert the character sequence hold by the input string to title case
+    !> Returns the titlecase version of the character sequence hold by the input string
     !>
-    !> This method is Elemental and returns a new string_type instance which holds titlecase
-    !> version of the character sequence hold by the input string
+    !> This method is Elemental and returns a new string_type instance which holds this
+    !> titlecase character sequence
     interface to_title
         module procedure :: to_title_string
     end interface to_title
 
-    !> Reverse the character sequence hold by the input string
+    !> Reverses the character sequence hold by the input string
     !> 
-    !> This method is Elemental and returns a new string_type instance which holds reversed
-    !> sequence of the character sequence hold by the input string
+    !> This method is Elemental and returns a new string_type instance which holds this
+    !> reverse character sequence
     interface reverse
         module procedure :: reverse_string
     end interface reverse

From 734551d6da65e0ab49f48c57913f6b6008ae1590 Mon Sep 17 00:00:00 2001
From: Aman Godara <amangodara891@gmail.com>
Date: Fri, 19 Mar 2021 17:49:06 +0530
Subject: [PATCH 11/12] improved documentation of to_title function

---
 doc/specs/stdlib_string_type.md | 4 +++-
 src/stdlib_ascii.f90            | 6 +++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/doc/specs/stdlib_string_type.md b/doc/specs/stdlib_string_type.md
index 7a4472397..63c38ccf4 100644
--- a/doc/specs/stdlib_string_type.md
+++ b/doc/specs/stdlib_string_type.md
@@ -1136,7 +1136,9 @@ end program demo
 
 #### Description
 
-Returns a new string_type instance which holds the titlecase version of the character sequence hold by the input string.
+Returns a new string_type instance which holds the titlecase (or capitalized) version of the character sequence hold by the input string.
+Capitalized version: The first alphabetical character of the input character sequence is transformed to uppercase unless it 
+follows a numeral and the rest of the characters in the sequence are transformed to lowercase.
 
 #### Syntax
 
diff --git a/src/stdlib_ascii.f90 b/src/stdlib_ascii.f90
index d797d33b1..e446f29e2 100644
--- a/src/stdlib_ascii.f90
+++ b/src/stdlib_ascii.f90
@@ -79,15 +79,15 @@ module stdlib_ascii
         module procedure :: to_upper
     end interface to_upper
 
-    !> Returns a new character sequence which is the titled
+    !> Returns a new character sequence which is the title case
     !> version of the input character sequence
     !> This method is pure and returns a character sequence
     interface to_title
         module procedure :: to_title
     end interface to_title
 
-    !> Returns a new character sequence which is the reversed
-    !> version of the input charater sequence
+    !> Returns a new character sequence which is reverse of
+    !> the input charater sequence
     !> This method is pure and returns a character sequence
     interface reverse
         module procedure :: reverse

From 060db2d33923fa95a6b04ba300175e4ce98e17f4 Mon Sep 17 00:00:00 2001
From: Sebastian Ehlert <28669218+awvwgk@users.noreply.github.com>
Date: Fri, 19 Mar 2021 18:19:04 +0100
Subject: [PATCH 12/12] Reorder function exports

---
 src/stdlib_string_type.f90 | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/stdlib_string_type.f90 b/src/stdlib_string_type.f90
index 3a30513ef..2b46a5de9 100644
--- a/src/stdlib_string_type.f90
+++ b/src/stdlib_string_type.f90
@@ -19,9 +19,9 @@ module stdlib_string_type
     private
 
     public :: string_type
-    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, &
-              adjustl, to_lower, to_upper, to_title, reverse
+    public :: len, len_trim, trim, index, scan, verify, repeat, adjustr, adjustl
     public :: lgt, lge, llt, lle, char, ichar, iachar
+    public :: to_lower, to_upper, to_title, reverse
     public :: assignment(=)
     public :: operator(>), operator(>=), operator(<), operator(<=)
     public :: operator(==), operator(/=), operator(//)