2a/3: Continuous Assignment.

   // Continuous assignments define combinational logic circuit:
   assign a = (g) ? 33 : b * c;
   assign b = d + e;

• Order of continuous assignments is un-important,
• Loop free, otherwise: parasitic level-sensitive latches are formed (e.g. RS latch),
• Right-hand side's may range over rich operators (e.g. mux ?: and multiply *),
• Bit inserts to vectors are allowed on left-hand sides (but not combinational array writes).

    assign   d[31:1] = e[30:0];
    assign   d[0] = 0;
  

12: (C) 2008-13, DJ Greaves, University of Cambridge, Computer Laboratory.

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