WJP Here's a procedure that validates color specifications, both names and hexadecimal RGB specs. IsColorSpecQ returns 1 if its argument is either a recognized X11 color name or a well formed hexadecimal RGB specification. If so desired, the two routines on which it is based, IsColorNameQ and IsColorNumericQ can also be exported.
namespace eval validcolor {
namespace export IsColorSpecQ;
variable CN;
set CN([list ghost white]) 1; set CN([list white smoke]) 1; set CN([list floral white]) 1;
set CN([list antique white]) 1; set CN([list old lace]) 1; set CN([list papaya whip]) 1
set CN([list blanched almond]) 1; set CN([list peach puff]) 1; set CN([list navajo white]) 1
set CN([list lemon chiffon]) 1; set CN([list mint cream]) 1; set CN([list alice blue]) 1
set CN([list lavender blush]) 1; set CN([list misty rose]) 1; set CN([list dark slate gray]) 1
set CN([list dark slate grey]) 1; set CN([list dim gray]) 1; set CN([list dim grey]) 1
set CN([list slate gray]) 1; set CN([list slate grey]) 1; set CN([list light slate gray]) 1
set CN([list light slate grey]) 1; set CN([list light grey]) 1; set CN([list light gray]) 1
set CN([list midnight blue]) 1; set CN([list navy blue]) 1; set CN([list cornflower blue]) 1
set CN([list dark slate blue]) 1; set CN([list slate blue]) 1; set CN([list medium slate blue]) 1
set CN([list light slate blue]) 1; set CN([list medium blue]) 1; set CN([list royal blue]) 1
set CN([list dodger blue]) 1; set CN([list deep sky blue]) 1; set CN([list sky blue]) 1
set CN([list light sky blue]) 1; set CN([list steel blue]) 1; set CN([list light steel blue]) 1
set CN([list light blue]) 1; set CN([list powder blue]) 1; set CN([list pale turquoise]) 1
set CN([list dark turquoise]) 1; set CN([list medium turquoise]) 1; set CN([list light cyan]) 1
set CN([list cadet blue]) 1; set CN([list medium aquamarine]) 1; set CN([list dark green]) 1
set CN([list dark olive green]) 1; set CN([list dark sea green]) 1; set CN([list sea green]) 1
set CN([list medium sea green]) 1; set CN([list light sea green]) 1; set CN([list pale green]) 1
set CN([list spring green]) 1; set CN([list lawn green]) 1; set CN([list medium spring green]) 1
set CN([list green yellow]) 1; set CN([list lime green]) 1; set CN([list yellow green]) 1
set CN([list forest green]) 1; set CN([list olive drab]) 1; set CN([list dark khaki]) 1
set CN([list pale goldenrod]) 1; set CN([list light goldenrod yellow]) 1; set CN([list light yellow]) 1
set CN([list light goldenrod]) 1; set CN([list dark goldenrod]) 1; set CN([list rosy brown]) 1
set CN([list indian red]) 1; set CN([list saddle brown]) 1; set CN([list sandy brown]) 1
set CN([list dark salmon]) 1; set CN([list light salmon]) 1; set CN([list dark orange]) 1
set CN([list light coral]) 1; set CN([list orange red]) 1; set CN([list hot pink]) 1
set CN([list deep pink]) 1; set CN([list light pink]) 1; set CN([list pale violet red]) 1
set CN([list medium violet red]) 1; set CN([list violet red]) 1; set CN([list medium orchid]) 1
set CN([list dark orchid]) 1; set CN([list dark violet]) 1; set CN([list blue violet]) 1
set CN([list medium purple]) 1; set CN(snow) 1; set CN(GhostWhite) 1
set CN(WhiteSmoke) 1; set CN(gainsboro) 1; set CN(FloralWhite) 1
set CN(OldLace) 1; set CN(linen) 1; set CN(AntiqueWhite) 1
set CN(PapayaWhip) 1; set CN(BlanchedAlmond) 1; set CN(bisque) 1
set CN(PeachPuff) 1; set CN(NavajoWhite) 1; set CN(moccasin) 1
set CN(cornsilk) 1; set CN(ivory) 1; set CN(LemonChiffon) 1
set CN(seashell) 1; set CN(honeydew) 1; set CN(MintCream) 1
set CN(azure) 1; set CN(AliceBlue) 1; set CN(lavender) 1
set CN(LavenderBlush) 1; set CN(MistyRose) 1; set CN(white) 1
set CN(black) 1; set CN(DarkSlateGray) 1; set CN(DarkSlateGrey) 1
set CN(DimGray) 1; set CN(DimGrey) 1; set CN(SlateGray) 1
set CN(SlateGrey) 1; set CN(LightSlateGray) 1; set CN(LightSlateGrey) 1
set CN(gray) 1; set CN(grey) 1; set CN(LightGrey) 1
set CN(LightGray) 1; set CN(MidnightBlue) 1; set CN(navy) 1
set CN(NavyBlue) 1; set CN(CornflowerBlue) 1; set CN(DarkSlateBlue) 1
set CN(SlateBlue) 1; set CN(MediumSlateBlue) 1; set CN(LightSlateBlue) 1
set CN(MediumBlue) 1; set CN(RoyalBlue) 1; set CN(blue) 1
set CN(DodgerBlue) 1; set CN(DeepSkyBlue) 1; set CN(SkyBlue) 1
set CN(LightSkyBlue) 1; set CN(SteelBlue) 1; set CN(LightSteelBlue) 1
set CN(LightBlue) 1; set CN(PowderBlue) 1; set CN(PaleTurquoise) 1
set CN(DarkTurquoise) 1; set CN(MediumTurquoise) 1; set CN(turquoise) 1
set CN(cyan) 1; set CN(LightCyan) 1; set CN(CadetBlue) 1; set CN(MediumAquamarine) 1
set CN(aquamarine) 1; set CN(DarkGreen) 1; set CN(DarkOliveGreen) 1
set CN(DarkSeaGreen) 1; set CN(SeaGreen) 1; set CN(MediumSeaGreen) 1
set CN(LightSeaGreen) 1; set CN(PaleGreen) 1; set CN(SpringGreen) 1;
set CN(LawnGreen) 1; set CN(green) 1; set CN(chartreuse) 1
set CN(MediumSpringGreen) 1; set CN(GreenYellow) 1; set CN(LimeGreen) 1
set CN(YellowGreen) 1; set CN(ForestGreen) 1; set CN(OliveDrab) 1
set CN(DarkKhaki) 1; set CN(khaki) 1; set CN(PaleGoldenrod) 1
set CN(LightGoldenrodYellow) 1; set CN(LightYellow) 1; set CN(yellow) 1
set CN(gold) 1; set CN(LightGoldenrod) 1; set CN(goldenrod) 1
set CN(DarkGoldenrod) 1; set CN(RosyBrown) 1; set CN(IndianRed) 1
set CN(SaddleBrown) 1; set CN(sienna) 1; set CN(peru) 1
set CN(burlywood) 1; set CN(beige) 1; set CN(wheat) 1
set CN(SandyBrown) 1; set CN(tan) 1; set CN(chocolate) 1
set CN(firebrick) 1; set CN(brown) 1; set CN(DarkSalmon) 1
set CN(salmon) 1; set CN(LightSalmon) 1; set CN(orange) 1
set CN(DarkOrange) 1; set CN(coral) 1; set CN(LightCoral) 1
set CN(tomato) 1; set CN(OrangeRed) 1; set CN(red) 1
set CN(HotPink) 1; set CN(DeepPink) 1; set CN(pink) 1
set CN(LightPink) 1; set CN(PaleVioletRed) 1; set CN(maroon) 1
set CN(MediumVioletRed) 1; set CN(VioletRed) 1; set CN(magenta) 1
set CN(violet) 1; set CN(plum) 1; set CN(orchid) 1
set CN(MediumOrchid) 1; set CN(DarkOrchid) 1; set CN(DarkViolet) 1
set CN(BlueViolet) 1; set CN(purple) 1; set CN(MediumPurple) 1
set CN(thistle) 1; set CN(snow1) 1; set CN(snow2) 1
set CN(snow3) 1; set CN(snow4) 1; set CN(seashell1) 1
set CN(seashell2) 1; set CN(seashell3) 1; set CN(seashell4) 1
set CN(AntiqueWhite1) 1; set CN(AntiqueWhite2) 1; set CN(AntiqueWhite3) 1
set CN(AntiqueWhite4) 1; set CN(bisque1) 1; set CN(bisque2) 1
set CN(bisque3) 1; set CN(bisque4) 1; set CN(PeachPuff1) 1
set CN(PeachPuff2) 1; set CN(PeachPuff3) 1; set CN(PeachPuff4) 1
set CN(NavajoWhite1) 1; set CN(NavajoWhite2) 1; set CN(NavajoWhite3) 1
set CN(NavajoWhite4) 1; set CN(LemonChiffon1) 1; set CN(LemonChiffon2) 1
set CN(LemonChiffon3) 1; set CN(LemonChiffon4) 1; set CN(cornsilk1) 1
set CN(cornsilk2) 1; set CN(cornsilk3) 1; set CN(cornsilk4) 1
set CN(ivory1) 1; set CN(ivory2) 1; set CN(ivory3) 1
set CN(ivory4) 1; set CN(honeydew1) 1; set CN(honeydew2) 1
set CN(honeydew3) 1; set CN(honeydew4) 1; set CN(LavenderBlush1) 1
set CN(LavenderBlush2) 1; set CN(LavenderBlush3) 1; set CN(LavenderBlush4) 1
set CN(MistyRose1) 1; set CN(MistyRose2) 1; set CN(MistyRose3) 1
set CN(MistyRose4) 1; set CN(azure1) 1; set CN(azure2) 1
set CN(azure3) 1; set CN(azure4) 1; set CN(SlateBlue1) 1
set CN(SlateBlue2) 1; set CN(SlateBlue3) 1; set CN(SlateBlue4) 1
set CN(RoyalBlue1) 1; set CN(RoyalBlue2) 1; set CN(RoyalBlue3) 1
set CN(RoyalBlue4) 1; set CN(blue1) 1; set CN(blue2) 1
set CN(blue3) 1; set CN(blue4) 1; set CN(DodgerBlue1) 1
set CN(DodgerBlue2) 1; set CN(DodgerBlue3) 1; set CN(DodgerBlue4) 1
set CN(SteelBlue1) 1; set CN(SteelBlue2) 1; set CN(SteelBlue3) 1
set CN(SteelBlue4) 1; set CN(DeepSkyBlue1) 1; set CN(DeepSkyBlue2) 1
set CN(DeepSkyBlue3) 1; set CN(DeepSkyBlue4) 1; set CN(SkyBlue1) 1
set CN(SkyBlue2) 1; set CN(SkyBlue3) 1; set CN(SkyBlue4) 1
set CN(LightSkyBlue1) 1; set CN(LightSkyBlue2) 1; set CN(LightSkyBlue3) 1
set CN(LightSkyBlue4) 1; set CN(SlateGray1) 1; set CN(SlateGray2) 1
set CN(SlateGray3) 1; set CN(SlateGray4) 1; set CN(LightSteelBlue1) 1
set CN(LightSteelBlue2) 1; set CN(LightSteelBlue3) 1; set CN(LightSteelBlue4) 1
set CN(LightBlue1) 1; set CN(LightBlue2) 1; set CN(LightBlue3) 1
set CN(LightBlue4) 1; set CN(LightCyan1) 1; set CN(LightCyan2) 1
set CN(LightCyan3) 1; set CN(LightCyan4) 1; set CN(PaleTurquoise1) 1
set CN(PaleTurquoise2) 1; set CN(PaleTurquoise3) 1; set CN(PaleTurquoise4) 1
set CN(CadetBlue1) 1; set CN(CadetBlue2) 1; set CN(CadetBlue3) 1
set CN(CadetBlue4) 1; set CN(turquoise1) 1; set CN(turquoise2) 1
set CN(turquoise3) 1; set CN(turquoise4) 1; set CN(cyan1) 1
set CN(cyan2) 1; set CN(cyan3) 1; set CN(cyan4) 1
set CN(DarkSlateGray1) 1; set CN(DarkSlateGray2) 1; set CN(DarkSlateGray3) 1
set CN(DarkSlateGray4) 1; set CN(aquamarine1) 1; set CN(aquamarine2) 1
set CN(aquamarine3) 1; set CN(aquamarine4) 1; set CN(DarkSeaGreen1) 1
set CN(DarkSeaGreen2) 1; set CN(DarkSeaGreen3) 1; set CN(DarkSeaGreen4) 1
set CN(SeaGreen1) 1; set CN(SeaGreen2) 1; set CN(SeaGreen3) 1
set CN(SeaGreen4) 1; set CN(PaleGreen1) 1; set CN(PaleGreen2) 1
set CN(PaleGreen3) 1; set CN(PaleGreen4) 1; set CN(SpringGreen1) 1
set CN(SpringGreen2) 1; set CN(SpringGreen3) 1; set CN(SpringGreen4) 1
set CN(green1) 1; set CN(green2) 1; set CN(green3) 1
set CN(green4) 1; set CN(chartreuse1) 1; set CN(chartreuse2) 1
set CN(chartreuse3) 1; set CN(chartreuse4) 1; set CN(OliveDrab1) 1
set CN(OliveDrab2) 1; set CN(OliveDrab3) 1; set CN(OliveDrab4) 1
set CN(DarkOliveGreen1) 1; set CN(DarkOliveGreen2) 1; set CN(DarkOliveGreen3) 1
set CN(DarkOliveGreen4) 1; set CN(khaki1) 1; set CN(khaki2) 1
set CN(khaki3) 1; set CN(khaki4) 1; set CN(LightGoldenrod1) 1
set CN(LightGoldenrod2) 1; set CN(LightGoldenrod3) 1; set CN(LightGoldenrod4) 1
set CN(LightYellow1) 1; set CN(LightYellow2) 1; set CN(LightYellow3) 1
set CN(LightYellow4) 1; set CN(yellow1) 1; set CN(yellow2) 1
set CN(yellow3) 1; set CN(yellow4) 1; set CN(gold1) 1
set CN(gold2) 1; set CN(gold3) 1; set CN(gold4) 1
set CN(goldenrod1) 1; set CN(goldenrod2) 1; set CN(goldenrod3) 1
set CN(goldenrod4) 1; set CN(DarkGoldenrod1) 1; set CN(DarkGoldenrod2) 1
set CN(DarkGoldenrod3) 1; set CN(DarkGoldenrod4) 1; set CN(RosyBrown1) 1
set CN(RosyBrown2) 1; set CN(RosyBrown3) 1; set CN(RosyBrown4) 1
set CN(IndianRed1) 1; set CN(IndianRed2) 1; set CN(IndianRed3) 1
set CN(IndianRed4) 1; set CN(sienna1) 1; set CN(sienna2) 1
set CN(sienna3) 1; set CN(sienna4) 1; set CN(burlywood1) 1
set CN(burlywood2) 1; set CN(burlywood3) 1; set CN(burlywood4) 1
set CN(wheat1) 1; set CN(wheat2) 1; set CN(wheat3) 1
set CN(wheat4) 1; set CN(tan1) 1; set CN(tan2) 1
set CN(tan3) 1; set CN(tan4) 1; set CN(chocolate1) 1
set CN(chocolate2) 1; set CN(chocolate3) 1; set CN(chocolate4) 1
set CN(firebrick1) 1; set CN(firebrick2) 1; set CN(firebrick3) 1
set CN(firebrick4) 1; set CN(brown1) 1; set CN(brown2) 1
set CN(brown3) 1; set CN(brown4) 1; set CN(salmon1) 1
set CN(salmon2) 1; set CN(salmon3) 1; set CN(salmon4) 1
set CN(LightSalmon1) 1; set CN(LightSalmon2) 1; set CN(LightSalmon3) 1
set CN(LightSalmon4) 1; set CN(orange1) 1; set CN(orange2) 1
set CN(orange3) 1; set CN(orange4) 1; set CN(DarkOrange1) 1
set CN(DarkOrange2) 1; set CN(DarkOrange3) 1; set CN(DarkOrange4) 1
set CN(coral1) 1; set CN(coral2) 1; set CN(coral3) 1
set CN(coral4) 1; set CN(tomato1) 1; set CN(tomato2) 1
set CN(tomato3) 1; set CN(tomato4) 1; set CN(OrangeRed1) 1
set CN(OrangeRed2) 1; set CN(OrangeRed3) 1; set CN(OrangeRed4) 1
set CN(red1) 1; set CN(red2) 1; set CN(red3) 1
set CN(red4) 1; set CN(DeepPink1) 1; set CN(DeepPink2) 1
set CN(DeepPink3) 1; set CN(DeepPink4) 1; set CN(HotPink1) 1
set CN(HotPink2) 1; set CN(HotPink3) 1; set CN(HotPink4) 1
set CN(pink1) 1; set CN(pink2) 1; set CN(pink3) 1
set CN(pink4) 1; set CN(LightPink1) 1; set CN(LightPink2) 1
set CN(LightPink3) 1; set CN(LightPink4) 1; set CN(PaleVioletRed1) 1
set CN(PaleVioletRed2) 1; set CN(PaleVioletRed3) 1; set CN(PaleVioletRed4) 1
set CN(maroon1) 1; set CN(maroon2) 1; set CN(maroon3) 1
set CN(maroon4) 1; set CN(VioletRed1) 1; set CN(VioletRed2) 1
set CN(VioletRed3) 1; set CN(VioletRed4) 1; set CN(magenta1) 1
set CN(magenta2) 1; set CN(magenta3) 1; set CN(magenta4) 1
set CN(orchid1) 1; set CN(orchid2) 1; set CN(orchid3) 1
set CN(orchid4) 1; set CN(plum1) 1; set CN(plum2) 1
set CN(plum3) 1; set CN(plum4) 1; set CN(MediumOrchid1) 1
set CN(MediumOrchid2) 1; set CN(MediumOrchid3) 1; set CN(MediumOrchid4) 1
set CN(DarkOrchid1) 1; set CN(DarkOrchid2) 1; set CN(DarkOrchid3) 1
set CN(DarkOrchid4) 1; set CN(purple1) 1; set CN(purple2) 1
set CN(purple3) 1; set CN(purple4) 1; set CN(MediumPurple1) 1
set CN(MediumPurple2) 1; set CN(MediumPurple3) 1; set CN(MediumPurple4) 1
set CN(thistle1) 1; set CN(thistle2) 1; set CN(thistle3) 1
set CN(thistle4) 1; set CN(gray0) 1; set CN(grey0) 1
set CN(gray1) 1; set CN(grey1) 1; set CN(gray2) 1
set CN(grey2) 1; set CN(gray3) 1; set CN(grey3) 1
set CN(gray4) 1; set CN(grey4) 1; set CN(gray5) 1
set CN(grey5) 1; set CN(gray6) 1; set CN(grey6) 1
set CN(gray7) 1; set CN(grey7) 1; set CN(gray8) 1
set CN(grey8) 1; set CN(gray9) 1; set CN(grey9) 1
set CN(gray10) 1; set CN(grey10) 1; set CN(gray11) 1
set CN(grey11) 1; set CN(gray12) 1; set CN(grey12) 1
set CN(gray13) 1; set CN(grey13) 1; set CN(gray14) 1
set CN(grey14) 1; set CN(gray15) 1; set CN(grey15) 1
set CN(gray16) 1; set CN(grey16) 1; set CN(gray17) 1
set CN(grey17) 1; set CN(gray18) 1; set CN(grey18) 1
set CN(gray19) 1; set CN(grey19) 1; set CN(gray20) 1
set CN(grey20) 1; set CN(gray21) 1; set CN(grey21) 1
set CN(gray22) 1; set CN(grey22) 1; set CN(gray23) 1
set CN(grey23) 1; set CN(gray24) 1; set CN(grey24) 1
set CN(gray25) 1; set CN(grey25) 1; set CN(gray26) 1
set CN(grey26) 1; set CN(gray27) 1; set CN(grey27) 1
set CN(gray28) 1; set CN(grey28) 1; set CN(gray29) 1
set CN(grey29) 1; set CN(gray30) 1; set CN(grey30) 1
set CN(gray31) 1; set CN(grey31) 1; set CN(gray32) 1
set CN(grey32) 1; set CN(gray33) 1; set CN(grey33) 1
set CN(gray34) 1; set CN(grey34) 1; set CN(gray35) 1
set CN(grey35) 1; set CN(gray36) 1; set CN(grey36) 1
set CN(gray37) 1; set CN(grey37) 1; set CN(gray38) 1
set CN(grey38) 1; set CN(gray39) 1; set CN(grey39) 1
set CN(gray40) 1; set CN(grey40) 1; set CN(gray41) 1
set CN(grey41) 1; set CN(gray42) 1; set CN(grey42) 1
set CN(gray43) 1; set CN(grey43) 1; set CN(gray44) 1
set CN(grey44) 1; set CN(gray45) 1; set CN(grey45) 1
set CN(gray46) 1; set CN(grey46) 1; set CN(gray47) 1
set CN(grey47) 1; set CN(gray48) 1; set CN(grey48) 1
set CN(gray49) 1; set CN(grey49) 1; set CN(gray50) 1
set CN(grey50) 1; set CN(gray51) 1; set CN(grey51) 1
set CN(gray52) 1; set CN(grey52) 1; set CN(gray53) 1
set CN(grey53) 1; set CN(gray54) 1; set CN(grey54) 1
set CN(gray55) 1; set CN(grey55) 1; set CN(gray56) 1
set CN(grey56) 1; set CN(gray57) 1; set CN(grey57) 1
set CN(gray58) 1; set CN(grey58) 1; set CN(gray59) 1
set CN(grey59) 1; set CN(gray60) 1; set CN(grey60) 1
set CN(gray61) 1; set CN(grey61) 1; set CN(gray62) 1
set CN(grey62) 1; set CN(gray63) 1; set CN(grey63) 1
set CN(gray64) 1; set CN(grey64) 1; set CN(gray65) 1
set CN(grey65) 1; set CN(gray66) 1; set CN(grey66) 1
set CN(gray67) 1; set CN(grey67) 1; set CN(gray68) 1
set CN(grey68) 1; set CN(gray69) 1; set CN(grey69) 1
set CN(gray70) 1; set CN(grey70) 1; set CN(gray71) 1
set CN(grey71) 1; set CN(gray72) 1; set CN(grey72) 1
set CN(gray73) 1; set CN(grey73) 1; set CN(gray74) 1
set CN(grey74) 1; set CN(gray75) 1; set CN(grey75) 1
set CN(gray76) 1; set CN(grey76) 1; set CN(gray77) 1
set CN(grey77) 1; set CN(gray78) 1; set CN(grey78) 1
set CN(gray79) 1; set CN(grey79) 1; set CN(gray80) 1
set CN(grey80) 1; set CN(gray81) 1; set CN(grey81) 1
set CN(gray82) 1; set CN(grey82) 1; set CN(gray83) 1
set CN(grey83) 1; set CN(gray84) 1; set CN(grey84) 1
set CN(gray85) 1; set CN(grey85) 1; set CN(gray86) 1
set CN(grey86) 1; set CN(gray87) 1; set CN(grey87) 1
set CN(gray88) 1; set CN(grey88) 1; set CN(gray89) 1
set CN(grey89) 1; set CN(gray90) 1; set CN(grey90) 1
set CN(gray91) 1; set CN(grey91) 1; set CN(gray92) 1
set CN(grey92) 1; set CN(gray93) 1; set CN(grey93) 1
set CN(gray94) 1; set CN(grey94) 1; set CN(gray95) 1
set CN(grey95) 1; set CN(gray96) 1; set CN(grey96) 1
set CN(gray97) 1; set CN(grey97) 1; set CN(gray98) 1
set CN(grey98) 1; set CN(gray99) 1; set CN(grey99) 1
set CN(gray100) 1; set CN(grey100) 1;
proc IsColorNameQ {s} {
variable CN
if {[info exists CN($s)]} {
return 1;
} else {
return 0;
}
}
#RGB color specs can provide 8, 16, 24, or 32 bits for each of the three colors.
proc IsColorNumericQ {s} {
return [regexp \
{^\#([[:xdigit:]]{6}|[[:xdigit:]]{3}|[[:xdigit:]]{9}|[[:xdigit:]]{12})$} $s]
}
proc IsColorSpecQ {s} {
if {[IsColorNameQ $s]} {
return 1;
} elseif {[IsColorNumericQ $s]} {
return 1;
} else {
return 0;
}
}
package provide validcolor
}
#end of namespace validcolorDemo:
puts "validcolor::IscolorSpecQ red = [validcolor::IsColorSpecQ red]"
puts "validcolor::IscolorSpecQ reed = [validcolor::IsColorSpecQ reed]"
puts "validcolor::IscolorSpecQ {sky blue} = [validcolor::IsColorSpecQ {sky blue}]"
puts "validcolor::IscolorSpecQ \#FF0000 = [validcolor::IsColorSpecQ \#FF0000]"
puts "validcolor::IscolorSpecQ \#FF000 = [validcolor::IsColorSpecQ \#FF000]"
puts "validcolor::IscolorSpecQ \#FFF000000 = [validcolor::IsColorSpecQ \#FFF000000]"
puts "validcolor::IscolorSpecQ \#FG0000 = [validcolor::IsColorSpecQ \#FG0000]"
MG An easier way of doing this, to check for a valid Tk colourname (I'm not sure if that's the same as a valid X11 colourname or not) is to use:
proc validcolor2 {col {win .}} {
return [expr {![catch {winfo rgb $win $col}]}]
}
validcolor2 {sky blue}