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bugs - How to embed an image into a string?


Note: The bug described in the post is in Mathematica 9, and has been fixed in 10.0.


The documentation for String contains the following statements:




Strings can contain any sequence of ordinary and special characters:
…
Strings preserve internal formatting:
…
Strings can have any expression embedded:
…
"ab \[Integral]\!\(\*FractionBox[\(1\), \(x\)]\)\[DifferentialD]x cd"


Strings can contain graphics:
…

"ab \!\(\*\nGraphicsBox[DiskBox[{0, 0}],\nImageSize->{34., Automatic}]\) cd"



So I assumed that an image could be inserted anywhere in the string. I tried to copy images in different ways:



  • from other Mathematica notebook cells, explicitly Imported before

  • from web pages opened in a browser

  • from image editors e.g. Paint

  • taking screenshots


and paste them into expressions (as list elements, function arguments etc) and it all worked perfectly well. But when I try to paste images into string literals, then the string looks good (with the image embedded) in the input cell, but the expression gets corrupted when evaluated -- it is not even a String anymore:



(* In[1]:= *) logo = Import["https://wolfram.com/favicon.ico", "Image"]
(* Out[1]= *) 

(* In[2]:= *) Shallow["Mathematica ", 1] (* The image was copy-pasted from the previous cell *)
(* Out[2]//Shallow= *) Times[<<5>>]

Question 1: Is it a bug?


It is interesting that inserting plots into string literals works well.


I need a solution to insert images into strings programmatically. It could also serve as a workaround for this bug. I was not able to find a built-in function that does exactly this, so I tried to use "\!\(\*…\)" markup mentioned in the documentation for String. I was not able to find a documentation for this markup, so I started experimenting.


Question 2: Is there a complete documentation for this markup?


After several attempts, I ended up with the following function:



(* In[3]:= *) imageToString[image_Image] := 
    "\!\(\*" <> ToString[ToBoxes[image], InputForm] <> "\)";

(* In[4]:= *) "Mathematica " <> imageToString[logo]
(* Out[4]= *) Mathematica

It seems to do what I need.


Question 3: Are there any shortcomings in my implementation? Is there a more simple/standard way to do this?



Answer



You can convert any expression to string by using ToString. If you want to preserve the visual representation, you should use ToString[(*your expression*), StandardForm].



logo = Import["http://wolfram.com/favicon.ico", "Image"]
logostr = ToString[logo, StandardForm]
StringJoin["Mathematica", logostr]
% // StringQ

string with image


Edit:


By checking the cell expression of the paste-into cell, I think I'd like to agree with Simon's comment that it looks like a bug:


error parsed cell expression


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