Zim'sclassicbook"CodesandSecretWriting"beginswiththisexample ofaverysimplecryptogram:

   EAR LYTOB EDEAR LYTOR ISEM AKE SAM ANHEAL THYWEAL THYAN DWISEM

Ihaveactuallyprogrammedinlanguagesthatdisregardedwhitespacee ntirely.OldversionsofMicrosoftBASICforexampleusedaonelevelpa rserwhichdidnothaveaseparatetokenizer.Fortranalsoignoredwhit espace(asidefromthewhitespaceneededtogetyourcodeintotheright columnonthecard!)withtheunfortunateeffectthatthesetwostateme ntswereequivalent:

    do 20 i = 1. 10
    do20i = 1.10

Thefirstoneisanobvioustypoofthefollowing:

    do 20 i = 1, 10

Which,ifmymemorydoesnotfailme,istheoldFortranwayofwriting

    for (i = 1; i <= 10; i++) {

withline20beingthecorresponding"}".¶Ihopethiscommenthasbeenh elpfulinunderstandingwhySteveBournethoughtmakingwhitespacesi gnificantinhislanguagedesignwasagoodidea!

The "significant whitespace" here is a space between command-line arguments. For that to qualify, you'd also have to include C as such a language.

  long jmp();
  longjmp();