ifdef, if key is defined

source for Home/ByExample/XilizeMarkup/Signatures/Directives/ifdef :: index.xil

ifdef, if key is defined

See also &{link:ifndef} and &{link:if}.

ifdef. _DirName_ directory name ${_DirName_}

ifndef. _DirName_ directory name _DirName_ is not defined

ifdef. x value of key x is ${x}

ifndef. x key x is not defined

ifdef. _DirName_ {{

  directory name ${_DirName_}

}}

ifdef. x {{

  x value of key x is ${x}
  
  else. {{
    x is not defined
  }}

}}

ifndef. x {{

  x is not defined
  
  else. {{
    x value of key x is ${x}
  }}

}}

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