Compiler Directives - General Description
 Switch Directives: 
 {$A+} / {$A-}        Switches between Word and Byte alignment of variables
 {$B+} / {$B-}        Enables/Disables Boolean `Short Circuit' Evaluation
 {$D+} / {$D-}        Enables/Disables generation of debug information
 {$E+} / {$E-}        Enables/Disables 8087 Emulation routines
 {$F+} / {$F-}        Forces/Does not force Far Calls
 {$I+} / {$I-}        Enables/Disables I/O checking
 {$L+} / {$L-}        Enables/Disables geration of local symbols
 {$N+} / {$N-}        Enables/Disables use of the 8087 math chip
 {$O+} / {$O-}        Enables/Disables Overlay Code Generation
 {$R+} / {$R-}        Enables/Disables code generation for range checking
 {$S+} / {$S-}        Enables/Disables stack overflow checking
 {$V+} / {$V-}        Enables/Disables variable parameter string checking
 Parameter Directives: 
 {$I FileName}                    Includes external files when compiling
 {$L FileName}                    Link the file being compiled with FileName
 {$M StackSize,HeapMin,HeapMax}   Specifies memory allocation parameters
 {$O UnitName}                    Transforms a Unit into an overlay
 Conditional Compilation Directives: 
 {$DEFINE name}       Defines a conditional symbol with a given name
 {$UNDEF name}        Undefines a conditional symbol with a given name
 {$IFDEF name}        Compile following source if symbol is defined
 {$IFNDEF name}       Compile following source if symbol is not defined
 {$IFOPT switch}      Compile following source depending on a switch state
 {$ELSE}              Provides alternate compilation path from an {$IFxxx}
 {$ENDIF}             Terminates the conditional compile started by {$IFxxx}