From c45ff910f0790a3aeeccf10c855910f231a7f9b5 Mon Sep 17 00:00:00 2001
From: Grant Sanderson <grant@3blue1brown.com>
Date: Thu, 8 Apr 2021 14:46:03 -0700
Subject: [PATCH] Remove double brace convention, since it causes errors with a
 number of tex strings

---
 example_scenes.py                   | 30 ++++++++++++++++-------------
 manimlib/mobject/svg/tex_mobject.py |  6 ++----
 2 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/example_scenes.py b/example_scenes.py
index a005fee9..10484451 100644
--- a/example_scenes.py
+++ b/example_scenes.py
@@ -161,20 +161,24 @@ class TexTransformExample(Scene):
     def construct(self):
         to_isolate = ["B", "C", "=", "(", ")"]
         lines = VGroup(
-            # Surrounding substrings with double braces
-            # will ensure that those parts are separated
-            # out in the Tex.  For example, here the
-            # Tex will have 5 submobjects, corresponding
-            # to the strings [A^2, +, B^2, =, C^2]
-            Tex("{{A^2}} + {{B^2}} = {{C^2}}"),
-            Tex("{{A^2}} = {{C^2}} - {{B^2}}"),
+            # Passing in muliple arguments to Tex will result
+            # in the same expression as if those arguments had
+            # been joined together, except that the submobject
+            # heirarchy of the resulting mobject ensure that the
+            # Tex mobject has a subject corresponding to
+            # each of these strings.  For example, the Tex mobject
+            # below will have 5 subjects, corresponding to the
+            # expressions [A^2, +, B^2, =, C^2]
+            Tex("A^2", "+", "B^2", "=", "C^2"),
+            # Likewise here
+            Tex("A^2", "=", "C^2", "-", "B^2"),
             # Alternatively, you can pass in the keyword argument
             # "isolate" with a list of strings that should be out as
-            # their own submobject.  So both lines below are equivalent
-            # to what you'd get by wrapping every instance of "B", "C"
-            # "=", "(" and ")" with double braces
-            Tex("{{A^2}} = (C + B)(C - B)", isolate=to_isolate),
-            Tex("A = \\sqrt{(C + B)(C - B)}", isolate=to_isolate)
+            # their own submobject.  So the line below is equivalent
+            # to the commented out line below it.
+            Tex("A^2 = (C + B)(C - B)", isolate=["A^2", *to_isolate]),
+            # Tex("A^2", "=", "(", "C", "+", "B", ")", "(", "C", "-", "B", ")"),
+            Tex("A = \\sqrt{(C + B)(C - B)}", isolate=["A", *to_isolate])
         )
         lines.arrange(DOWN, buff=LARGE_BUFF)
         for line in lines:
@@ -233,7 +237,7 @@ class TexTransformExample(Scene):
         # new_line2 and the "\sqrt" from the final line.  By passing in,
         # transform_mismatches=True, it will transform this "^2" part into
         # the "\sqrt" part.
-        new_line2 = Tex("{{A}}^2 = (C + B)(C - B)", isolate=to_isolate)
+        new_line2 = Tex("A^2 = (C + B)(C - B)", isolate=["A", *to_isolate])
         new_line2.replace(lines[2])
         new_line2.match_style(lines[2])
 
diff --git a/manimlib/mobject/svg/tex_mobject.py b/manimlib/mobject/svg/tex_mobject.py
index 0818c4b1..8cebe1f5 100644
--- a/manimlib/mobject/svg/tex_mobject.py
+++ b/manimlib/mobject/svg/tex_mobject.py
@@ -172,14 +172,12 @@ class Tex(SingleStringTex):
             self.organize_submobjects_left_to_right()
 
     def break_up_tex_strings(self, tex_strings):
-        # Separate out anything surrounded in double braces
-        patterns = ["{{", "}}"]
         # Separate out any strings specified in the isolate
         # or tex_to_color_map lists.
-        patterns.extend([
+        patterns = (
             "({})".format(re.escape(ss))
             for ss in it.chain(self.isolate, self.tex_to_color_map.keys())
-        ])
+        )
         pattern = "|".join(patterns)
         pieces = []
         for s in tex_strings: