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arjenmarkusarjenmarkus
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Preliminary implementation of stringlist module
This commit introduces a very preliminary version of a module to handle lists of strings (that is: a structure containing strings of varying lengths)
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‎src/CMakeLists.txt

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@@ -37,6 +37,7 @@ set(SRC
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stdlib_error.f90
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stdlib_kinds.f90
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stdlib_logger.f90
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stdlib_stringlist.f90
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stdlib_system.F90
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${outFiles}
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)

‎src/stdlib_stringlist.f90

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! stringlist.f90 --
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! Module for storing and manipulating lists of strings
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! The strings may have arbitrary lengths, not necessarily the same
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!
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! Note: very preliminary
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!
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module stdlib_stringlists
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implicit none
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private
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integer, parameter, public :: list_head = 0
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integer, parameter, public :: list_end = -1
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public :: t_stringlist
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integer, parameter :: initial_size = 20
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type t_string
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character(len=:), allocatable :: value
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end type t_string
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type t_stringlist
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private
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integer :: size = 0
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type(t_string), dimension(:), allocatable :: string
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contains
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procedure :: insert => insert_string
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procedure :: get => get_string
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procedure :: length => length_list
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end type t_stringlist
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contains
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! length_list --
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! Return the size (length) of the list
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!
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! Arguments:
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! list The list of strings to retrieve the string from
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!
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integer function length_list( list )
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class(t_stringlist), intent(in) :: list
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length_list = list%size
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end function length_list
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! insert_string --
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! Insert a new string into the list
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!
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! Arguments:
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! list The list of strings where the new string should be inserted
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! idx Index after which to insert the string
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! string The string in question
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!
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subroutine insert_string( list, idx, string )
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class(t_stringlist), intent(inout) :: list
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integer, intent(in) :: idx
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character(len=*), intent(in) :: string
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integer :: i
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integer :: idxnew
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type(t_string) :: new_element
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type(t_string), dimension(:), allocatable :: empty_strings
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!
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! Initialise the list if necessary
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!
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if ( .not. allocated(list%string) ) then
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allocate( list%string(initial_size) )
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do i = 1,size(list%string)
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list%string(i)%value = ''
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enddo
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endif
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!
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! Check the index:
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! - if the index is list_head, then shift the entire array
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! - if the index is list_end or negative in general, determine the absolute index
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! - if the index is large than the registered size, expand the list
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! - shift everything after the absolute index
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!
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new_element%value = string
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if ( idx == list_head ) then
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list%size = list%size + 1
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list%string = [new_element, list%string]
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else
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idxnew = idx
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if ( idx <= list_end ) then
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idxnew = list%size - (abs(idx) - 1)
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if ( idxnew <= 0 ) then
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idxnew = 0
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endif
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endif
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if ( idxnew <= size(list%string) ) then
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list%size = max( idxnew+1, list%size + 1 )
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list%string = [list%string(1:idxnew), new_element, list%string(idxnew+1:)]
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else
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allocate( empty_strings(idxnew-size(list%string)) )
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do i = 1,size(empty_strings)
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empty_strings(i)%value = ''
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enddo
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list%string = [list%string, empty_strings, new_element]
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list%size = idxnew + 1
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endif
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endif
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end subroutine insert_string
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! get_string --
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! Get the string at a particular index
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!
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! Arguments:
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! list The list of strings to retrieve the string from
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! idx Index after which to insert the string
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!
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function get_string( list, idx )
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class(t_stringlist), intent(inout) :: list
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integer, intent(in) :: idx
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character(len=:), allocatable :: get_string
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integer :: idxnew
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type(t_string) :: new_element
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!
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! Examine the actual index:
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! - if the index is larger than the size, return an empty string
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! - if the index is equal to list_head, interpret it as index 1
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! - if the index is negative, calculate the absolute index
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!
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if ( idx > list%size ) then
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get_string = ''
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else
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idxnew = idx
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if ( idx == list_head ) then
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idxnew = 1
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elseif ( idx <= list_end ) then
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idxnew = list%size - (abs(idx) - 1)
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endif
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if ( idxnew < 1 ) then
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get_string = ''
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else
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get_string = list%string(idxnew)%value
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endif
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endif
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end function get_string
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end module stdlib_stringlists

‎src/tests/CMakeLists.txt

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@@ -15,6 +15,7 @@ add_subdirectory(optval)
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add_subdirectory(stats)
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add_subdirectory(system)
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add_subdirectory(quadrature)
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add_subdirectory(stringlist)
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ADDTEST(always_skip)
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set_tests_properties(always_skip PROPERTIES SKIP_RETURN_CODE 77)

‎src/tests/stringlist/CMakeLists.txt

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ADDTEST(stringlist)

‎src/tests/stringlist/test_stringlist.f90

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! test_stringlist.f90 --
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! Test program for the stdlib_stringlist module
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!
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! Straightforward test program: try to cover "all" special cases
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!
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program test_stringlists
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use stdlib_stringlists
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implicit none
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type(t_stringlist) :: list
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integer :: i
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!
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! The straightforward cases: insert a few strings and retrieve them
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!
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call list%insert( list_head, "C" )
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call list%insert( list_head, "B" )
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call list%insert( list_head, "A" )
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!
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! Now insert a string at an arbitrary location - it will be at position 11
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!
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call list%insert( 10, "Number 10" )
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!
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! Append a string to the end of the list - that will be position 12
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!
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call list%insert( list_end, "Appended" )
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!
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! Insert a string near the end of the list - that will be position 12-2+1
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!
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call list%insert( list_end-2, "Appended 2" )
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!
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! Insert a string beyond the beginning - that should appear at the start
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!
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call list%insert( list_end-30, "Effectively prepended" )
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!
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! Print the result
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!
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do i = 1,list%length()
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write(*,*) i, '>', list%get(i), '<'
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enddo
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!
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! And select two elements at the end
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!
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write(*,*) 'end-1' , '>', list%get(list_end-1), '<'
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write(*,*) 'end' , '>', list%get(list_end), '<'
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write(*,*) 'end-30', '>', list%get(list_end-30), '<'
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!
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! Okay, finally set an element really far and read it back
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!
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call list%insert( 40, "Really far away" )
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write(*,*) '40', '>', list%get(40), '<'
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write(*,*) '41', '>', list%get(41), '<'
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write(*,*) list%length()
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end program test_stringlists

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