Commit Friday evening.

PDFA and EXFO Laser are now part of the family

Functions/helper_functions_community/mat2tikz/test/private/StreamMaker.m

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+function SM = StreamMaker()
+% StreamMaker (Factory for fie/input/output Streams)
+%
+% A StreamMaker can make Stream PseudoObjects based on either
+%  an "fid" or "filename" (and extra arguments for `fopen`).
+% The StreamMaker also contains a method `isStream` to validate whether
+% the value passed is a valid stream specifier.
+%
+% Usage
+%
+%  SM = StreamMaker;
+%
+%    Stream = SM.make(fid)
+%    Stream = SM.make(filename, ...)
+%
+% This returns a PseudoObject Stream with the following properties:
+%   - name: (file) name of the stream
+%   - fid: handle (fid) of the stream
+%
+% and methods:
+%   - print: prints to the stream, i.e. fprintf
+%   - close: closes the stream, i.e. fclose
+%
+% It may also contain a field to automatically close the Stream when it goes
+% out of scope.
+%
+    SM = PseudoObject('StreamMaker', ...
+                      'isStream',  @isStream, ...
+                      'make', @constructStream);
+end
+
+function PseudoObj = PseudoObject(T, varargin)
+% construct a Pseudo-Object with type T (no other fields yet)
+    PseudoObj = struct('Type', T, varargin{:});
+end
+
+function bool = isStream(value)
+    bool = ischar(value) || ismember(value, [1,2,fopen('all')]);
+    %TODO: allow others kinds of streams
+    %     Stream -> clipboard (write on close)
+    %     Stream -> string variable
+    % e.g. a quick-and-dirty way would be to write the file to `tempname`
+    % putting a flag to read that file back upon completion.
+end
+
+function Stream = constructStream(streamSpecifier, varargin)
+    % this is the actual constructor of a stream
+    if ~isStream(streamSpecifier)
+        error('StreamMaker:NotAStream', 'Invalid stream specifier "%s"', ...
+              streamSpecifier);
+    end
+
+    Stream = PseudoObject('Stream');
+    closeAfterUse = false;
+    if ischar(streamSpecifier)
+        Stream.name = streamSpecifier;
+        Stream.fid = fopen(Stream.name, varargin{:});
+        closeAfterUse = true;
+    elseif isnumeric(streamSpecifier)
+        Stream.fid  = streamSpecifier;
+        Stream.name = fopen(Stream.fid);
+    end
+
+    if Stream.fid == -1
+        error('Stream:InvalidStream', ...
+              'Unable to create stream "%s"!', streamSpecifier);
+    end
+
+    Stream.print = @(varargin) fprintf(Stream.fid, varargin{:});
+    Stream.close = @() fclose(Stream.fid);
+    if closeAfterUse
+        Stream.closeAfterUse = onCleanup(Stream.close);
+    end
+end