Joining Group - Reh

Reh is a joining group value that indicates how the Arabic letter reh, along with its variants like rreh and nyala-reh, connects to adjacent characters in script rendering. It defines the specific cursive behavior for these letters, which are primarily right-joining, meaning they connect to the preceding character but not to the following one, creating a distinctive gap in the word. This value helps shape the correct visual form of text in languages such as Arabic, Persian, and Urdu, ensuring that reh-like letters maintain their characteristic loop and tail without forming a ligature on the left side. The joining group also accounts for contextual forms in different positions, though the core behavior remains consistent across scripts that use these glyphs.