added range feature for get, added shift function

src/stdlib_stringlist_type.f90

@@ -84,18 +84,20 @@ module stdlib_stringlist_type
  insert_before_chararray_int, &
  insert_before_stringarray_int
 
- procedure :: get_string_idx => get_string_idx_impl
- generic, public :: get => get_string_idx
+ procedure :: get_idx => get_idx_impl
+ procedure :: get_range_idx => get_range_idx_impl
+ generic, public :: get => get_idx, &
+ get_range_idx
 
- procedure :: pop_idx => pop_idx_impl
- procedure :: pop_range_idx => pop_range_idx_impl
- generic, public :: pop => pop_idx,  &
- pop_range_idx
+ procedure :: pop_idx =>  pop_idx_impl
+ procedure :: pop_range_idx =>  pop_range_idx_impl
+ generic, public :: pop =>  pop_idx, &
+  pop_range_idx
 
- procedure :: drop_idx => drop_idx_impl
- procedure :: drop_range_idx => drop_range_idx_impl
- generic, public :: drop => drop_idx,  &
- drop_range_idx
+ procedure :: drop_idx =>  drop_idx_impl
+ procedure :: drop_range_idx =>  drop_range_idx_impl
+ generic, public :: drop =>  drop_idx, &
+  drop_range_idx
 
  end type stringlist_type
 
@@ -453,6 +455,21 @@ pure logical function ineq_sarray_stringlist( lhs, rhs )
 
  end function ineq_sarray_stringlist
 
+ ! Version: experimental
+ !>
+ !> Shifts a stringlist_index by integer 'shift_by'
+ !> Returns the shifted stringlist_index
+ pure function shift( idx, shift_by )
+ !> Not a part of public API
+ type(stringlist_index_type), intent(in) :: idx
+ integer, intent(in) :: shift_by
+
+ type(stringlist_index_type), intent(in) :: shift
+
+ shift = merge( fidx( idx%offset + shift_by ), bidx( idx%offset + shift_by ), idx%forward )
+
+ end function shift
+
  ! clear:
 
  !> Version: experimental
@@ -588,7 +605,7 @@ end subroutine insert_at_stringarray_idx_wrap
  !>
  !> Inserts 'positions' number of empty positions BEFORE integer index 'idxn'
  !> Modifies the input stringlist 'list'
- subroutine insert_before_empty_positions( list, idxn, positions )
+ subroutine insert_before_engine( list, idxn, positions )
  !> Not a part of public API
  class(stringlist_type), intent(inout) :: list
  integer, intent(inout) :: idxn
@@ -618,7 +635,7 @@ subroutine insert_before_empty_positions( list, idxn, positions )
 
  end if
 
- end subroutine insert_before_empty_positions
+ end subroutine insert_before_engine
 
  !> Version: experimental
  !>
@@ -633,7 +650,7 @@ subroutine insert_before_string_int_impl( list, idxn, string )
  integer :: work_idxn
 
  work_idxn = idxn
- call insert_before_empty_positions( list, work_idxn, 1 )
+ call insert_before_engine( list, work_idxn, 1 )
 
  list%stringarray(work_idxn) = string
 
@@ -688,7 +705,7 @@ subroutine insert_before_chararray_int_impl( list, idxn, carray )
  integer :: work_idxn, idxnew
 
  work_idxn = idxn
- call insert_before_empty_positions( list, work_idxn, size( carray ) )
+ call insert_before_engine( list, work_idxn, size( carray ) )
 
  do i = 1, size( carray )
  idxnew = work_idxn + i - 1
@@ -711,7 +728,7 @@ subroutine insert_before_stringarray_int_impl( list, idxn, sarray )
  integer :: work_idxn, idxnew
 
  work_idxn = idxn
- call insert_before_empty_positions( list, work_idxn, size( sarray ) )
+ call insert_before_engine( list, work_idxn, size( sarray ) )
 
  do i = 1, size( sarray )
  idxnew = work_idxn + i - 1
@@ -722,68 +739,113 @@ end subroutine insert_before_stringarray_int_impl
 
  ! get:
 
+ !> Version: experimental
+ !>
+ !> Returns strings present at stringlist_indexes in interval ['first', 'last']
+ !> Stores requested strings in array 'capture_strings'
+ !> No return
+ subroutine get_engine( list, first, last, capture_strings )
+ class(stringlist_type) :: list
+ type(stringlist_index_type), intent(in) :: first, last
+ type(string_type), allocatable, intent(out) :: capture_strings(:)
+
+ integer :: from, to
+ integer :: i, inew
+
+ from = max( list%to_current_idxn( first ), 1 )
+ to = min( list%to_current_idxn( last ), list%len() )
+
+ ! out of bounds indexes won't be captured in capture_strings
+ if ( from <= to ) then
+ pos = to - from + 1
+ allocate( capture_strings(pos) )
+
+ inew = 1
+ do i = from, to
+ capture_strings(inew) = list%stringarray(i)
+ inew = inew + 1
+ end do
+
+ else
+ allocate( capture_strings(0) )
+ end if
+
+ end subroutine get_engine
+
  !> Version: experimental
  !>
  !> Returns the string present at stringlist_index 'idx' in stringlist 'list'
  !> Returns string_type instance
- pure function get_string_idx_impl( list, idx )
- class(stringlist_type), intent(in) :: list
- type(stringlist_index_type), intent(in) :: idx
- type(string_type) :: get_string_idx_impl
-
- integer :: idxn
+ pure function get_idx_impl( list, idx )
+ class(stringlist_type), intent(in) :: list
+ type(stringlist_index_type), intent(in) :: idx
+ type(string_type) :: get_idx_impl
 
- idxn = list%to_current_idxn( idx )
+ type(string_type), allocatable :: capture_strings(:)
 
- ! if the index is out of bounds, returns a string_type instance equivalent to empty string
- if ( 1 <= idxn .and. idxn <= list%len() ) then
- get_string_idx_impl = list%stringarray(idxn)
+ call get_engine( list, idx, idx, capture_strings )
 
+ ! if index 'idx' is out of bounds, returns an empty string
+ if ( size(capture_strings) == 1 ) then
+ call move( capture_strings(1), get_idx_impl )
  end if
 
- end function get_string_idx_impl
+ end function get_idx_impl
+
+ !> Version: experimental
+ !>
+ !> Returns strings present at stringlist_indexes in interval ['first', 'last']
+ !> Returns array of string_type instances
+ pure function get_range_idx_impl( list, first, last )
+ class(stringlist_type), intent(in) :: list
+ type(stringlist_index_type), intent(in) :: first, last
+
+ type(string_type), allocatable :: get_range_idx_impl(:)
+
+ call get_engine( list, first, last, get_range_idx_impl )
+
+ end function get_range_idx_impl
+
+ ! pop & drop:
 
  !> Version: experimental
  !>
  !> Removes strings present at indexes in interval ['first', 'last']
- !> Returns captured popped strings
- subroutine pop_engine( list, first, last, capture_popped)
+ !> Stores captured popped strings in array 'capture_popped'
+ !> No return
+ subroutine pop_drop_engine( list, first, last, capture_popped )
  class(stringlist_type) :: list
  type(stringlist_index_type), intent(in) :: first, last
  type(string_type), allocatable, intent(out), optional :: capture_popped(:)
 
- integer :: firstn, lastn
- integer :: i, inew
- integer :: pos, old_len, new_len
+ integer :: firstn, lastn, from, to
+ integer :: i, inew, pos, old_len, new_len
  type(string_type), dimension(:), allocatable :: new_stringarray
 
  old_len = list%len()
-
- firstn = max( list%to_current_idxn( first ), 1 )
- lastn = min( list%to_current_idxn( last ), old_len )
+ firstn = list%to_current_idxn( first )
+ lastn = list%to_current_idxn( last )
+ from = max( firstn , 1 )
+ to = min( lastn , old_len )
 
  ! out of bounds indexes won't modify stringlist
- if ( firstn <= lastn ) then
- pos = lastn - firstn + 1
+ if ( from <= to ) then
+ pos  = to - from + 1
  new_len = old_len - pos
 
  allocate( new_stringarray(new_len) )
- do i = 1, firstn - 1
+ do i = 1, from - 1
  call move( list%stringarray(i), new_stringarray(i) )
  end do
 
  ! capture popped strings
  if ( present(capture_popped) ) then
- allocate( capture_popped(pos) )
- inew = 1
- do i = firstn, lastn
- call move( list%stringarray(i), capture_popped(inew) )
- inew = inew + 1
- end do
+ call get_engine( list, shift( first, from - firstn ), &
+ & shift( last, lastn - to ), capture_popped )
  end if
 
- inew = firstn
- do i = lastn + 1, old_len
+ inew = from
+ do i = to + 1, old_len
  call move( list%stringarray(i), new_stringarray(inew) )
  inew = inew + 1
  end do
@@ -795,9 +857,7 @@ subroutine pop_engine( list, first, last, capture_popped)
  end if
  end if
 
- end subroutine pop_engine
-
- ! pop:
+ end subroutine pop_drop_engine
 
  !> Version: experimental
  !>
@@ -810,10 +870,10 @@ function pop_idx_impl( list, idx )
 
  type(string_type), dimension(:), allocatable :: popped_strings
 
- call pop_engine( list, idx, idx, popped_strings )
+ call pop_drop_engine( list, idx, idx, popped_strings )
 
  if ( size(popped_strings) == 1 ) then
- pop_idx_impl = popped_strings(1)
+ call move( pop_idx_impl, popped_strings(1) )
  end if
 
  end function pop_idx_impl
@@ -829,12 +889,10 @@ function pop_range_idx_impl( list, first, last )
 
  type(string_type), dimension(:), allocatable :: pop_range_idx_impl
 
- call pop_engine( list, first, last, pop_range_idx_impl )
+ call pop_drop_engine( list, first, last, pop_range_idx_impl )
 
  end function pop_range_idx_impl
 
- ! drop:
-
  !> Version: experimental
  !>
  !> Removes the string present at stringlist_index 'idx' in stringlist 'list'
@@ -843,7 +901,7 @@ subroutine drop_idx_impl( list, idx )
  class(stringlist_type) :: list
  type(stringlist_index_type), intent(in) :: idx
 
- call pop_engine( list, idx, idx )
+ call pop_drop_engine( list, idx, idx )
 
  end subroutine drop_idx_impl
 
@@ -852,11 +910,11 @@ end subroutine drop_idx_impl
  !> Removes strings present at stringlist_indexes in interval ['first', 'last']
  !> in stringlist 'list'
  !> Doesn't return removed strings
- subroutine drop_range_idx_impl( list, first, last)
+ subroutine drop_range_idx_impl( list, first, last )
  class(stringlist_type) :: list
  type(stringlist_index_type), intent(in) :: first, last
 
- call pop_engine( list, first, last )
+ call pop_drop_engine( list, first, last )
 
  end subroutine drop_range_idx_impl