You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: subsasgn.m
    path of file: ./repos/bspm/thirdparty/spm8/@gifti
    
    the code of the file until where you have to start completion: function this = subsasgn(this, subs, A)
% Subscript assignment for GIfTI objects
%__________________________________________________________________________

    
function this = subsasgn(this, subs, A)
% Subscript assignment for GIfTI objects
%__________________________________________________________________________
% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

% Guillaume Flandin
% $Id: subsasgn.m 3999 2010-07-19 10:54:18Z guillaume $

switch subs(1).type
    case '.'
        if ~ismember(subs(1).subs, {'vertices' 'faces' 'normals' 'cdata','mat','private'})
            error('Reference to non-existent field ''%s''.',subs(1).subs);
        else
            % TODO % handle cases when length(subs) > 1
            [i,n] = isintent(this,subs(1).subs);
            if isempty(i) && ~strcmp(subs(1).subs,'private')
                n = length(this.data) + 1;
                % TODO % Initialise data field appropriately
                this.data{n}.metadata = struct([]);
                this.data{n}.space    = [];
                this.data{n}.attributes.Dim = size(A);
                % TODO % set DataType according to intent type
                this.data{n}.data = [];
                switch subs(1).subs
                    case {'vertices','mat'}
                        in = 'NIFTI_INTENT_POINTSET';
                        dt = 'NIFTI_TYPE_FLOAT32';
                        this.data{n}.space.DataSpace = 'NIFTI_XFORM_UNKNOWN';
                        this.data{n}.space.TransformedSpace = 'NIFTI_XFORM_UNKNOWN';
                        this.data{n}.space.MatrixData = eye(4);
                    case 'faces'
                        in = 'NIFTI_INTENT_TRIANGLE';
                        dt = 'NIFTI_TYPE_INT32';
                    case 'normals'
                        in = 'NIFTI_INTENT_VECTOR';
                        dt = 'NIFTI_TYPE_FLOAT32';
                    case 'cdata'
                        in = 'NIFTI_INTENT_NONE';
                        dt = 'NIFTI_TYPE_FLOAT32';
                    otherwise
                        error('This should not happen.');
                end