shifted slice from stdlib_ascii to stdlib_strings and modified module dependencies accordingly

Author: aman-godara

src/Makefile.manual

@@ -56,9 +56,7 @@ $(SRCGEN): %.f90: %.fypp common.fypp
 
 # Fortran module dependencies
 f18estop.o: stdlib_error.o
-stdlib_ascii.o: \
-	stdlib_kinds.o \
-	stdlib_math.o
+stdlib_ascii.o: stdlib_kinds.o
 stdlib_bitsets.o: stdlib_kinds.o
 stdlib_bitsets_64.o: stdlib_bitsets.o
 stdlib_bitsets_large.o: stdlib_bitsets.o
@@ -114,6 +112,9 @@ stdlib_stats_var.o: \
 stdlib_stats_distribution_PRNG.o: \
         stdlib_kinds.o \
 	stdlib_error.o
-stdlib_string_type.o: stdlib_ascii.o stdlib_kinds.o
-stdlib_strings.o: stdlib_ascii.o stdlib_string_type.o
+stdlib_string_type.o: stdlib_ascii.o \
+	stdlib_kinds.o
+stdlib_strings.o: stdlib_ascii.o \
+	stdlib_string_type.o \
+	stdlib_math.o
 stdlib_math.o: stdlib_kinds.o

src/stdlib_ascii.fypp

@@ -6,7 +6,6 @@
 !> The specification of this module is available [here](../page/specs/stdlib_ascii.html).
 module stdlib_ascii
     use stdlib_kinds, only : int8, int16, int32, int64
-    use stdlib_math, only: clip
 
     implicit none
     private
@@ -21,7 +20,7 @@ module stdlib_ascii
 
     ! Character conversion functions
     public :: to_lower, to_upper, to_title, to_sentence, reverse
-    public :: to_string, slice
+    public :: to_string
 
     !> Version: experimental
     !>
@@ -361,59 +360,6 @@ contains
 
     end function reverse
 
-    pure function slice(string, first, last, stride, include_last) result(sliced_string)
-        character(len=*), intent(in) :: string
-        integer, intent(in), optional :: first, last, stride
-        logical, intent(in), optional :: include_last
-        integer :: first_index, last_index, stride_vector, n, i, j
-        character(len=:), allocatable :: sliced_string
-
-        first_index = 1
-        last_index = len(string)
-        stride_vector = 1
-        if (len(string) > 0) then
-            if (present(stride)) then
-                if (stride /= 0) then
-                    if (stride < 0) then
-                        first_index = len(string)
-                        last_index = 1
-                    end if
-                    stride_vector = stride
-                end if
-            else
-                if (present(first) .and. present(last)) then
-                    if (last < first) then
-                        stride_vector = -1
-                    end if
-                end if
-            end if
-
-            if (present(first)) then
-                first_index =  clip(first, 1, len(string))
-            end if
-            if (present(last)) then
-                last_index = clip(last, 1, len(string))
-            end if
-
-            n = int((last_index - first_index) / stride_vector)
-            allocate(character(len=max(0, n + 1)) :: sliced_string)
-            
-            if (present(include_last)) then
-                if (include_last) then
-                    first_index = last_index - (n * stride_vector)
-                end if
-            end if
-
-            j = 1
-            do i = first_index, last_index, stride_vector
-                sliced_string(j:j) = string(i:i)
-                j = j + 1
-            end do
-        else
-            sliced_string = ''
-        end if
-    end function slice
-
     #:for kind in INT_KINDS
     !> Represent an integer of kind ${kind}$ as character sequence
     pure function to_string_integer_${kind}$(val) result(string)

src/stdlib_strings.f90

@@ -6,11 +6,13 @@
 module stdlib_strings
     use stdlib_ascii, only : whitespace
     use stdlib_string_type, only : string_type, char, verify
+    use stdlib_math, only: clip
     implicit none
     private
 
     public :: strip, chomp
     public :: starts_with, ends_with
+    public :: slice
 
 
     !> Remove leading and trailing whitespace characters.
@@ -56,7 +58,13 @@ module stdlib_strings
         module procedure :: ends_with_string_char
         module procedure :: ends_with_char_string
         module procedure :: ends_with_char_char
-    end interface ends_with
+    end interface 
+    
+    !> 
+    interface slice
+        module procedure :: slice_string
+        module procedure :: slice_char
+    end interface slice
 
 
 contains
@@ -290,5 +298,72 @@ elemental function ends_with_string_string(string, substring) result(match)
 
     end function ends_with_string_string
 
+    !> Slices the region between first and last indexes of the input
+    !> string by taking strides of length stride
+    elemental function slice_string(string, first, last, stride, include_last) result(sliced_string)
+        type(string_type), intent(in) :: string
+        integer, intent(in), optional :: first, last, stride
+        logical, intent(in), optional :: include_last
+        type(string_type) :: sliced_string
+
+        sliced_string = string_type(slice(char(string), first, last, stride, include_last))
+
+    end function slice_string
+
+    !> Slices the region between first and last indexes of the input
+    !> character sequence by taking strides of length stride
+    pure function slice_char(string, first, last, stride, include_last) result(sliced_string)
+        character(len=*), intent(in) :: string
+        integer, intent(in), optional :: first, last, stride
+        logical, intent(in), optional :: include_last
+        integer :: first_index, last_index, stride_vector, n, i, j
+        character(len=:), allocatable :: sliced_string
+
+        first_index = 1
+        last_index = len(string)
+        stride_vector = 1
+        if (len(string) > 0) then
+            if (present(stride)) then
+                if (stride /= 0) then
+                    if (stride < 0) then
+                        first_index = len(string)
+                        last_index = 1
+                    end if
+                    stride_vector = stride
+                end if
+            else
+                if (present(first) .and. present(last)) then
+                    if (last < first) then
+                        stride_vector = -1
+                    end if
+                end if
+            end if
+
+            if (present(first)) then
+                first_index =  clip(first, 1, len(string))
+            end if
+            if (present(last)) then
+                last_index = clip(last, 1, len(string))
+            end if
+
+            n = int((last_index - first_index) / stride_vector)
+            allocate(character(len=max(0, n + 1)) :: sliced_string)
+            
+            if (present(include_last)) then
+                if (include_last) then
+                    first_index = last_index - (n * stride_vector)
+                end if
+            end if
+
+            j = 1
+            do i = first_index, last_index, stride_vector
+                sliced_string(j:j) = string(i:i)
+                j = j + 1
+            end do
+        else
+            sliced_string = ''
+        end if
+    end function slice_char
+
 
 end module stdlib_strings