*! version 1.0.0  26sep97  STB-41 ip23

program define ifexp
     version 5.0

local if "required"
local options "noVARlabel noVALlabel noUNabbrev noSPace Color(str)"
parse "`*'"
parse "`if'", parse(" ><=&|!()")

if "`color'" == "" {local color = "b"}    /* set display color */
local color = lower(substr("`color'",1,1))
if index("wbgyr","`color'") == 0 {local color = "b"}

if "`if'" != "" {
  local ifst "  if "                   /* handle leading "if " */
  local lif = 5
  macro shift

  if "`space'" != "nospace" {                 /* set up space  */
    local sp " "
    local sp1 = 1
    }
  else { local sp1 = 0 }

  di
  while "`1'" != "" {             /* start main loop on tokens */

    capture confirm variable `1'                 /* var name ? */
    local rc _rc  

    local m = 0
    local n = length("`1'")
    if `n' + `lif' > 78 {               /* no room for token ? */
      di in `color' "`ifst'"
      local ifst ">    "
      local lif = 5
      local n = 0
    }
                                             /* is punctuation */
    if "`1'" == "==" { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "<=" { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == ">=" { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "!=" { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "<"  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == ">"  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "="  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "&"  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "|"  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "!"  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == "("  { local ifst "`ifst'`1'`sp'" }
    else if "`1'" == ")"  { local ifst "`ifst'`1'`sp'" }

    else if `rc' == 0 {                  /* is a variable name */
      local tif "`1'"
      if "`unabbrev'" != "nounabbrev" {      /* allow unabbrev */
        unabbrev `1'
        local tif "$S_1"
        }
      if "`varlabel'" != "novarlabel" {   /* allow var label ? */
        local vrl : variable label `1'
        *di "`vrl'"
        if "`vrl'" != "" { local tif "`vrl'" }  /* var label ? */
        }
      local m = length("`tif'")         /* no room for token ? */
      if `m' + `lif' > 78 {
        di in `color' "`ifst'"
        local ifst ">    "
        local lif = 5
        local m = 0
      }
      local ifst "`ifst'`tif'`sp'"
      local vll : value label `1'
    }

    else {                                       /* is a value */
      local tif "`1'"                   /* allow value label ? */
      if "`vll'" != "" & "`vallabel'" != "novallabel" {
        local lv : label `vll' `1'
        if "`lv'" != "" { local tif "`lv'" }  /* value label ? */
      }

      local m = length("`tif'")         /* no room for token ? */
      if `m' + `lif' > 78 {
        di in `color' "`ifst'"
        local ifst ">    "
        local lif = 5
        local m = 0
      }
      local ifst "`ifst'`tif'`sp'"
    }
                                        /* set new line length */
    if `m' > 0 { local lif = `lif' + `m' + `sp1' }
    else { local lif = `lif' + `n' + `sp1' }
    macro shift                                  /* next token */
  }                                 /* end main loop on tokens */

di in `color' "`ifst'"                  /* display expanded if */

exit
end