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Add std::string support
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‎CMakeLists.txt

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@@ -165,10 +165,16 @@ endfunction()
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# Four SWIG libraries
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swig_fortran_add_module(flc "${FLIBCPP_VERSION_CPP}")
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swig_fortran_add_module(flc_random)
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target_link_libraries(flc_random flc)
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swig_fortran_add_module(flc_algorithm)
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target_link_libraries(flc_algorithm flc_random flc)
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swig_fortran_add_module(flc_random)
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target_link_libraries(flc_random flc)
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swig_fortran_add_module(flc_string)
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target_link_libraries(flc_string flc)
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swig_fortran_add_module(flc_vector)
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target_link_libraries(flc_vector flc)
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‎doc/interface.rst

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.. literalinclude:: ../src/flc_random.i
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:linenos:
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flc_string
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=============
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.. literalinclude:: ../src/flc_string.i
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:linenos:
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flc_vector
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=============
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‎doc/modules/algorithm.rst

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.. _argsort: https://docs.scipy.org/doc/numpy-1.15.0/reference/generated/numpy.argsort.html
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.. _modules_algorithm_searching:
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Searching
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=========
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‎doc/modules/string.rst

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String
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******
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String manipulation is not yet implemented.
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The string module includes the ``String`` derived type and a handful of string
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conversion functions.
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String type
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===========
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The C++ standard library "string" is a dynamically resizable, mutable character
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array.
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Construction and destruction
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----------------------------
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Strings are constructed using three interface functions:
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- The function without arguments creates an empty string;
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- An integer argument ``count`` and a single character will create a string
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of size ``count`` filled with that character; and
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- A standard Fortran ``character(kind=C_CHAR, len=*)`` which will be copied
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to the string.
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Here are three examples of initialization::
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use flc_string, only : String
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type(String) :: v
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s = String()
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! s%size() == 0
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s = String(10, "!")
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! s%size() == 10
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! s%get(i) == "!"
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s = String("I am a string!")
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Modification
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------------
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Like :ref:`vectors <modules_Vector>`, Strings can be resized dynamically using
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a variety of methods:
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- ``resize`` to specify an exact size;
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- ``push_back`` to add a new character to the end of it;
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- ``append`` to add another string to the end
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- ``pop_back`` to remove the last character;
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- ``clear`` to remove all elements.
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The string also has a ``set`` bound subroutine for assigning a character to a
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specified index::
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type(String) :: s
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s = String("=", 10)
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call s%set(1, "8")
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call s%set(s%size(), "D")
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.. important:: Unlike the C++ version of this class, **strings in Flibcpp
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use 1-offset indexing**. This means that ``s%get(1)`` is the same as the C++
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``s[0]``: it returns the first element (i.e. the element with an offset of
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zero).
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Access
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------
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The size of a string is returned by the bound function ``size``; ``get``
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returns the character at an index; and ``front`` and ``back`` are aliases for
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``get(1)`` and ``get(v%size())``, respectively.
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Search
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------
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The ``find`` bound function will search for a substring, starting at an
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optional position. Like the :ref:`search
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algorithms <modules_algorithm_searching>` in Flibcpp, a search result of `0`
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indicates "not found" and any other result is the 1-offset index in the
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string. ::
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type(String) :: s
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integer :: i
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s = String("meowmeow")
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i = s%find("meow") ! Returns 1
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i = s%find("meow", 3) ! Returns 5
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i = s%find("woof") ! Returns 0
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View as an array pointer
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------------------------
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The string can be viewed (and indeed modified) as an array of character
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elements::
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type(String) :: s
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character, dimension(:), pointer :: charptr
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s = String("Hello!")
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charptr => s%view()
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charptr(6) = "?" ! change greeting to a question
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Conversion to native string
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---------------------------
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The ``str`` type-bound function returns an allocated character string::
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character(len=:), allocatable :: native
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type(String) :: s
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s = String("Hello world")
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native = s%str()
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write(0,"(a)") native
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Conversion functions
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====================
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The ``flc_string`` module includes several module procedures for converting
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native Fortran strings to integers and real numbers. These functions are robust
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and exception-safe, allowing intelligent error handling from the Fortran side.
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- Integer conversion: ``stoi``, ``stol``, ``stoll``
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- Real conversion: ``stof``, ``stod``
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::
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use flc, only : ierr, get_serr, SWIG_OverflowError, SWIG_ValueError
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use flc_string
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implicit none
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integer(4) :: temp
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character(len=100) :: tempstr
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read(*, '(a)') tempstr
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temp = stoi(trim(tempstr))
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if (ierr == SWIG_OverflowError) then
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write(0,*) "Your integer is too darn big!"
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elseif (ierr == SWIG_ValueError) then
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write(0,*) "That thing you entered? It wasn't an integer."
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end if
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.. ############################################################################
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.. end of doc/modules/string.rst

‎doc/modules/vector.rst

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@@ -52,7 +52,7 @@ the end of the vector (increasing the size by one) with ``push_back``. The
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removes a specific vector index or range of indices. ``clear`` removes
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all elements. Finally, ``set`` sets the value of an element at a given index.
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.. important:: Unlike the C++ version of this class, **all vectors in flibcpp
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.. important:: Unlike the C++ version of this class, **all vectors in Flibcpp
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use 1-offset indexing**. This means that ``v%get(1)`` is the same as the C++
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``v[0]``: it returns the first element (i.e. the element with an offset of
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zero).

‎src/flc_string.i

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/*!
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* \file flc_string.i
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*
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* Copyright (c) 2019 Oak Ridge National Laboratory, UT-Battelle, LLC.
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* Distributed under an MIT open source license: see LICENSE for details.
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*/
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%module "flc_string"
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%include "import_flc.i"
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// SWIG always represents std::string as native strings. We load its typemaps
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// but will explicitly create the class.
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%include <std_string.i>
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// Include typemaps for integer offsets and native integer types
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%include <std_common.i>
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// Typemap to convert positions from npos -> 0 and 1-offset otherwise
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%apply int FORTRAN_INT { std::size_t POSITION };
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%typemap(out, noblock=1) std::size_t POSITION {
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$result = ($1 == std::string::npos ? 0 : $1 + 1);
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}
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namespace std {
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class string {
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public:
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// >>> TYPES
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typedef size_t size_type;
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typedef ptrdiff_t difference_type;
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typedef char value_type;
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typedef const char& const_reference;
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// Typemaps for making std::vector feel more like native Fortran:
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// - Use Fortran 1-offset indexing
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%apply int FORTRAN_INDEX {size_type pos,
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size_type index,
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size_type start_index,
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size_type stop_index};
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// - Use native Fortran integers in proxy code
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%apply int FORTRAN_INT {size_type};
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// - Use fortran indexing (and 0 for not found) for search
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%apply std::size_t POSITION {size_type find};
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// - Allow access as an array view
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%apply SWIGTYPE& { string& view };
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%fortran_array_pointer(char, string& view);
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%typemap(out, noblock=1) string& view {
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$result.data = ($1->empty() ? NULL : const_cast<char*>($1->data()));
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$result.size = $1->size();
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}
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// - Allow interaction with other string objects
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%apply SWIGTYPE& {const string& OTHER};
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public:
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// >>> MEMBER FUNCTIONS
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// TODO: add more constructors
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string();
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string(size_type count, value_type ch);
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string(const std::string& s);
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// Accessors
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size_type size() const;
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bool empty() const;
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const_reference front() const;
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const_reference back() const;
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// Modify
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void resize(size_type count);
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void resize(size_type count, value_type v);
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void assign(const string& s);
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void push_back(value_type v);
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void pop_back();
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void clear();
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// String operations
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size_type find(const string& s, size_type pos = 0);
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void append(const string& s);
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int compare(const string& OTHER);
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// >>> EXTENSIONS
85+
// (TODO: add the same erase/insert extensions as std::vector)
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%extend {
88+
%fragment("SWIG_check_range");
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90+
void set(size_type index, value_type v) {
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SWIG_check_range(index, $self->size(),
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"std::string::set",
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return);
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(*$self)[index] = v;
95+
}
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97+
value_type get(size_type index) {
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SWIG_check_range(index, $self->size(),
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"std::string::get",
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return $self->front());
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return (*$self)[index];
102+
}
103+
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// Get a character array view
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string& view() { return *$self; }
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// Get a copy as a native Fortran string
108+
const string& str() { return *$self; }
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}
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};
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%exception {
113+
SWIG_check_unhandled_exception();
114+
try {
115+
$action
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}
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catch (const std::invalid_argument& e) {
118+
SWIG_exception(SWIG_ValueError, e.what());
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}
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catch (const std::out_of_range& e) {
121+
SWIG_exception(SWIG_OverflowError, e.what());
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}
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}
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// String conversion
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int stoi(const std::string& s);
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long stol(const std::string& s);
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long long stoll(const std::string& s);
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float stof(const std::string& s);
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double stod(const std::string& s);
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} // namespace std

‎src/generated/flc.f90

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integer(C_SIZE_T), public :: size = 0
2222
end type
2323
public :: get_serr
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integer(C_INT), parameter, public :: SWIG_UnknownError = -1_C_INT
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integer(C_INT), parameter, public :: SWIG_IOError = -2_C_INT
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integer(C_INT), parameter, public :: SWIG_RuntimeError = -3_C_INT
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integer(C_INT), parameter, public :: SWIG_IndexError = -4_C_INT
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integer(C_INT), parameter, public :: SWIG_TypeError = -5_C_INT
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integer(C_INT), parameter, public :: SWIG_DivisionByZero = -6_C_INT
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integer(C_INT), parameter, public :: SWIG_OverflowError = -7_C_INT
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integer(C_INT), parameter, public :: SWIG_SyntaxError = -8_C_INT
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integer(C_INT), parameter, public :: SWIG_ValueError = -9_C_INT
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integer(C_INT), parameter, public :: SWIG_SystemError = -10_C_INT
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integer(C_INT), parameter, public :: SWIG_AttributeError = -11_C_INT
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integer(C_INT), parameter, public :: SWIG_MemoryError = -12_C_INT
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integer(C_INT), parameter, public :: SWIG_NullReferenceError = -13_C_INT
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public :: get_flibcpp_version
2538
integer(C_INT), protected, public, &
2639
bind(C, name="flibcpp_version_major") :: flibcpp_version_major

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