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Examples of Potential Numbers

As examples, the tokens in Figure 2-10 are potential numbers, but they are not actually numbers, and so are reserved tokens; a conforming implementation is permitted, but not required, to define their meaning.

  1b5000                       777777q                1.7J  -3/4+6.7J  12/25/83  
  27^19                      3^4/5                6//7  3.1.2.6    ^-43^   
  3.141_592_653_589_793_238_4  -3.7+2.6i-6.17j+19.6k  


                     Figure 2--10: Examples of reserved tokens                   

The tokens in Figure 2-11 are not potential numbers; they are always treated as symbols:

  /     /5     +  1+  1-     
  foo+  ab.cd  _  ^   ^/-  


  Figure 2--11: Examples of symbols

The tokens in Figure 2-12 are potential numbers if the current input base is 16, but they are always treated as symbols if the current input base is 10.

  bad-face  25-dec-83  a/b  fad_cafe  f^ 


  Figure 2--12: Examples of symbols or potential numbers