user42151: In my sketch I have the following:
#define HU_ADDR                 0x190;
#define ALL_AUDIO_ADDR          0x1FF;
#define MY_ADDR                 0x360;
#define UNKNOWN_ADDR            0xFFF;

typedef byte MessageID;
enum {
  ACT_UNKNOWN,
  ACT_POWERON,
  ACT_POWEROFF,
  ACT_PASSIVEOFF_0,
  ACT_PASSIVEOFFRARE_0,
  ACT_PASSIVEON_0,
  ACT_KEYTURN,
  ACT_PRESSDISC
};

struct MessageDef {
  MessageID ID;
  word MasterAddr;
  word SlaveAddr;
  byte PayloadLength;
  byte Payload[20];
  char Description[20];
};

MessageDef MessageTable[] = {
  {ACT_POWERON,           HU_ADDR, UNKNOWN_ADDR, 13,  {0x00, 0x60, 0x31, 0xF1, 0x01, 0x01, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "On call"},
  {ACT_POWEROFF,          HU_ADDR, UNKNOWN_ADDR, 13,  {0x00, 0x60, 0x31, 0xF1, 0x00, 0x00, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "off?"},
  {ACT_PASSIVEOFF_0,      HU_ADDR, UNKNOWN_ADDR, 3,   {0x00, 0x11, 0x01},                                                                               "Passive: Weak"},
  {ACT_PASSIVEOFFRARE_0,  HU_ADDR, UNKNOWN_ADDR, 4,   {0x00, 0x11, 0x01, 0x20},                                                                         "Passive: Strong"}, 
  {ACT_PASSIVEON_0,       HU_ADDR, UNKNOWN_ADDR, 16,  {0x00, 0x74, 0x31, 0xF1, 0x80, 0x13, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x03, 0x03}, "On response"},
  {ACT_KEYTURN,           HU_ADDR, UNKNOWN_ADDR, 11,  {0x31, 0x62, 0x31, 0xF1, 0x00, 0xF8, 0xFF, 0xFF, 0xFF, 0xFF, 0x00},                               "Key turned"}, 
  {ACT_PRESSDISC,         HU_ADDR, UNKNOWN_ADDR, 4,   {0x00, 0x62, 0x31, 0x9F},                                                                         "DISC pressed"}
};

When I compile this, for some reason the Arduino IDE points at the first line and says "expected '}' before ';' token". If I replace the text like so:
#define HU_ADDR                 0x190;
#define ALL_AUDIO_ADDR          0x1FF;
#define MY_ADDR                 0x360;
#define UNKNOWN_ADDR            0xFFF;

typedef byte MessageID;
enum {
  ACT_UNKNOWN,
  ACT_POWERON,
  ACT_POWEROFF,
  ACT_PASSIVEOFF_0,
  ACT_PASSIVEOFFRARE_0,
  ACT_PASSIVEON_0,
  ACT_KEYTURN,
  ACT_PRESSDISC
};

struct MessageDef {
  MessageID ID;
  word MasterAddr;
  word SlaveAddr;
  byte PayloadLength;
  byte Payload[20];
  char Description[20];
};

MessageDef MessageTable[] = {
  {ACT_POWERON,           0x190, 0xFFF, 13,  {0x00, 0x60, 0x31, 0xF1, 0x01, 0x01, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "On call"},
  {ACT_POWEROFF,          0x190, 0xFFF, 13,  {0x00, 0x60, 0x31, 0xF1, 0x00, 0x00, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "off?"},
  {ACT_PASSIVEOFF_0,      0x190, 0xFFF, 3,   {0x00, 0x11, 0x01},                                                                               "Passive: Weak"},
  {ACT_PASSIVEOFFRARE_0,  0x190, 0xFFF, 4,   {0x00, 0x11, 0x01, 0x20},                                                                         "Passive: Strong"}, 
  {ACT_PASSIVEON_0,       0x190, 0xFFF, 16,  {0x00, 0x74, 0x31, 0xF1, 0x80, 0x13, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x03, 0x03}, "On response"},
  {ACT_KEYTURN,           0x190, 0xFFF, 11,  {0x31, 0x62, 0x31, 0xF1, 0x00, 0xF8, 0xFF, 0xFF, 0xFF, 0xFF, 0x00},                               "Key turned"}, 
  {ACT_PRESSDISC,         0x190, 0xFFF, 4,   {0x00, 0x62, 0x31, 0x9F},                                                                         "DISC pressed"}
};

Then it compiles with no complaints.
....what? Why? Aren't these functionally identical? Why does the compiler care if I use HU_ADDR instead of 0x190?

user-1: Don't put a semi-colon at the end of #define.
Whatever comes after #define NAME will be used to replace NAME across the source code.

42151: <p>In my sketch I have the following:</p>

<pre><code>#define HU_ADDR                 0x190;
#define ALL_AUDIO_ADDR          0x1FF;
#define MY_ADDR                 0x360;
#define UNKNOWN_ADDR            0xFFF;

typedef byte MessageID;
enum {
  ACT_UNKNOWN,
  ACT_POWERON,
  ACT_POWEROFF,
  ACT_PASSIVEOFF_0,
  ACT_PASSIVEOFFRARE_0,
  ACT_PASSIVEON_0,
  ACT_KEYTURN,
  ACT_PRESSDISC
};

struct MessageDef {
  MessageID ID;
  word MasterAddr;
  word SlaveAddr;
  byte PayloadLength;
  byte Payload[20];
  char Description[20];
};

MessageDef MessageTable[] = {
  {ACT_POWERON,           HU_ADDR, UNKNOWN_ADDR, 13,  {0x00, 0x60, 0x31, 0xF1, 0x01, 0x01, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "On call"},
  {ACT_POWEROFF,          HU_ADDR, UNKNOWN_ADDR, 13,  {0x00, 0x60, 0x31, 0xF1, 0x00, 0x00, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "off?"},
  {ACT_PASSIVEOFF_0,      HU_ADDR, UNKNOWN_ADDR, 3,   {0x00, 0x11, 0x01},                                                                               "Passive: Weak"},
  {ACT_PASSIVEOFFRARE_0,  HU_ADDR, UNKNOWN_ADDR, 4,   {0x00, 0x11, 0x01, 0x20},                                                                         "Passive: Strong"}, 
  {ACT_PASSIVEON_0,       HU_ADDR, UNKNOWN_ADDR, 16,  {0x00, 0x74, 0x31, 0xF1, 0x80, 0x13, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x03, 0x03}, "On response"},
  {ACT_KEYTURN,           HU_ADDR, UNKNOWN_ADDR, 11,  {0x31, 0x62, 0x31, 0xF1, 0x00, 0xF8, 0xFF, 0xFF, 0xFF, 0xFF, 0x00},                               "Key turned"}, 
  {ACT_PRESSDISC,         HU_ADDR, UNKNOWN_ADDR, 4,   {0x00, 0x62, 0x31, 0x9F},                                                                         "DISC pressed"}
};
</code></pre>

<p>When I compile this, for some reason the Arduino IDE points at the first line and says "expected '}' before ';' token". If I replace the text like so:</p>

<pre><code>#define HU_ADDR                 0x190;
#define ALL_AUDIO_ADDR          0x1FF;
#define MY_ADDR                 0x360;
#define UNKNOWN_ADDR            0xFFF;

typedef byte MessageID;
enum {
  ACT_UNKNOWN,
  ACT_POWERON,
  ACT_POWEROFF,
  ACT_PASSIVEOFF_0,
  ACT_PASSIVEOFFRARE_0,
  ACT_PASSIVEON_0,
  ACT_KEYTURN,
  ACT_PRESSDISC
};

struct MessageDef {
  MessageID ID;
  word MasterAddr;
  word SlaveAddr;
  byte PayloadLength;
  byte Payload[20];
  char Description[20];
};

MessageDef MessageTable[] = {
  {ACT_POWERON,           0x190, 0xFFF, 13,  {0x00, 0x60, 0x31, 0xF1, 0x01, 0x01, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "On call"},
  {ACT_POWEROFF,          0x190, 0xFFF, 13,  {0x00, 0x60, 0x31, 0xF1, 0x00, 0x00, 0x81, 0x00, 0x03, 0x01, 0x00, 0x00, 0x00},                   "off?"},
  {ACT_PASSIVEOFF_0,      0x190, 0xFFF, 3,   {0x00, 0x11, 0x01},                                                                               "Passive: Weak"},
  {ACT_PASSIVEOFFRARE_0,  0x190, 0xFFF, 4,   {0x00, 0x11, 0x01, 0x20},                                                                         "Passive: Strong"}, 
  {ACT_PASSIVEON_0,       0x190, 0xFFF, 16,  {0x00, 0x74, 0x31, 0xF1, 0x80, 0x13, 0x10, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x03, 0x03}, "On response"},
  {ACT_KEYTURN,           0x190, 0xFFF, 11,  {0x31, 0x62, 0x31, 0xF1, 0x00, 0xF8, 0xFF, 0xFF, 0xFF, 0xFF, 0x00},                               "Key turned"}, 
  {ACT_PRESSDISC,         0x190, 0xFFF, 4,   {0x00, 0x62, 0x31, 0x9F},                                                                         "DISC pressed"}
};
</code></pre>

<p>Then it compiles with no complaints.
....what? Why? Aren't these functionally identical? Why does the compiler care if I use HU_ADDR instead of 0x190?</p>
 -1: <p>Don't put a semi-colon at the end of #define.</p>

<p>Whatever comes after <code>#define NAME</code> will be used to replace NAME across the source code.</p>
