easyhtml
This lesson presents one type of function, the text function. As its name suggests, this type of function deals with texts. Unlike other functions, a text with built-in code serves as the basis for text functions.
Example 1
Display a color palette, which is frequently used for creating an HTML page. Save data as an HTML file.First, determine the number of colors displayed in one line using the define command.
define {
lcount = 12
}
Note that such constant quantities are called macros. The dollar sign '$' is used before the name in order to run them.
Let's tackle the last point first.
func color< main >
{
str out
out @ colorhtm()
out.write( "color.htm" )
shell( "color.htm" )
}
out @ colorhtm()
text colorhtm
...
\{
int vrgb i j k
uint cur
subfunc outitem
{
str rgb
rgb.out4( "%06X", vrgb )
@ item( rgb )
if ++cur == $lcount
{
@"</TR><TR>"
cur = 0
}
}
for i = 0xFF, i >= 0, i -= 0x33
{
for j = 0xFF, j >= 0, j -= 0x33
{
for k = 0xFF, k >= 0, k -= 0x33
{
vrgb = ( i << 16 ) + ( j << 8 ) + k
outitem()
}
}
}
for vrgb = 0xFFFFFF, vrgb >= 0, vrgb -= 0x111111 : outitem()
for vrgb = 0xFF0000, vrgb > 0, vrgb -= 0x110000 : outitem()
for vrgb = 0x00FF00, vrgb > 0, vrgb -= 0x001100 : outitem()
for vrgb = 0x0000FF, vrgb > 0, vrgb -= 0x000011 : outitem()
}
...
\!The \{...} command is used to insert the code into a text. outitem minorant function is defined like thisas:
rgb.out4( "%06X", vrgb )
@ item( rgb )Here, using the local variable named vrgb, the string is created that contains the hexadecimal representation, then another text function item is called for outputting the cell with the indicated color. The unary operator @ is used to output into the current string or, if there is no string to the console. Then, we determine the total number of cells in the row and add a new row to the table where approriate.
We use three embedded color cycles for searching possible values. Red, green or blue color components are affected by color cycling. Then these color components are arranged in the vrgb variable and we call the minorant function described above.
The next four color cycles display additional palette entries for gray, red, green and blue colors.
The \! command indicates the termination of a text function. By default, a text function works until the end of the file.
Let's take an example - a text function of cell entries.
We want a function that works like this:
text item( str rgb )
<TD ALIGN=CENTER><TABLE BGCOLOR=#\(rgb) WIDTH=60><TR><TD> </TD></TR></TABLE>
<FONT FACE="Courier">\(rgb)</FONT>
</TD>
\!As you can see, this is an HTML text that outputs the rgb color parameter. It is used as the background color of a table cell and for the display of its value output under the table cell.