less than in expression (#1917)

resolves #1909

Co-authored-by: Fred Lefévère-Laoide <Fred.Lefevere-Laoide@Taipy.io>

taipy/gui/_renderers/_markdown/preproc.py

@@ -61,7 +61,7 @@ class _Preprocessor(MdPreprocessor):
     __PROPERTY_RE = re.compile(r"((?:don'?t|not?)\s+)?([a-zA-Z][\.a-zA-Z_$0-9]*(?:\[(?:.*?)\])?)\s*(?:=(.*))?$")
 
     # Error syntax detection regex
-    __MISSING_LEADING_PIPE_RE = re.compile(r"<[^|](.*?)\|>")
+    __MISSING_LEADING_PIPE_RE = re.compile(r"^<[^|](.*?)\|>")
 
     _gui: "Gui"