Description:
the engine works by converting a template (which is a string, or a file) into a Tcl script, and then running it.Each line of text encountered will be returned as is. Exception is text between <% ... %> which is treated as Tcl code (the eval happens into regular interp)
Why not expand?
expand is a simple and snugly for Tcl language, be mounted in tcllib. You can use it as quick as flash.
But, that library has a problem, when to really use. we cannot write easily following signs { }.
Why not TemplaTcl?
TemplaTcl is a powerful and cool template engine.
But now, we cannot use it on Tcl8.4 :(
tmpl_parser is
a simple and fast template engine. That still not have function to read a file, create a parser object.
But we can use it instant, only write a command require or source.
Usage:
first, let's create a template file (templtest.tmpl):
<table><% for {set i 0} {$i < 4} {incr i} { %> <tr> <td><%= $i %></td> </tr><% } %> </table> <ul> <% foreach item $cityList { %><li><%= $item %> <% } %> </ul>
the above template (in HTML language) generates a 4-row table, and an unordered list, taking values from a $cityList variable, that we're going to define. First let's load the code:
source tmpl_parser.tcl
reading template file.
set fd [open templtest.tmpl r] set tmpl [read $fd] close $fd
now create a parser instance:
set parser [::tmpl_parser::tmpl_parser $tmpl]
set the variables used in our template:
set cityList {Ragusa Ravenna Rieti Rimini Rome Rovigo}
and render the template:
puts [eval $parser]
Here's the output that gets produced:
<table> <tr> <td>1</td> </tr> <tr> <td>2</td> </tr> <tr> <td>3</td> </tr> <tr> <td>4</td> </tr> </table> <ul> <li>Ragusa <li>Ravenna <li>Rieti <li>Rimini <li>Rome <li>Rovigo </ul>
# tmpl_parser.tcl # # Tcl embeddedd script parser(a template engine) # # This module comverts Tcl embeddedd scripts into a Tcl normal script(parser), # after you just have to do eval command for the generated parser. # # Copyright (c) 2007 by Kanryu KATO<[email protected]> # licensed on Tcl License.
package require Tcl 8.3 package provide tmpl_parser 0.1
namespace eval ::tmpl_parser {
namespace export tmpl_parser
}
proc ::tmpl_parser::tmpl_parser {tmpl} {
# Tcl enbedded tags # [[outer <%...inner...%> outer]] <-$tmpl # [ = ] <-$token # cd ef hi j <-indexes set parser { {set _o {}} } while {[set i [string first %> $tmpl]] != -1} { set h [expr $i-1] set j [expr $i+2] set token [string range $tmpl 0 $h] set d [string first <% $token] set c [expr $d-1] set e [expr $d+2] set f [expr $d+3] # outer lappend parser [escaped_parse [string range $token 0 $c]] switch [string index $token $e] { "=" { # normal expression (e.g. Thanks <%=$count%> accesses!) lappend parser [normal_parse [string range $token $f end]] } ":" { # numeric expression (e.g. <%:$i+2000%>) lappend parser [numeric_parse [string range $token $f end]] } default { # enbedded Tcl command is passed through listing lappend parser [string range $token $e end] } } # after "%>" set tmpl [string range $tmpl $j end] } #last outer lappend parser [escaped_parse $tmpl] lappend parser {join $_o ""} return [join $parser "\n"]
}
proc ::tmpl_parser::escaped_parse {str} {
set str [string map {\" \\\" \{ \\\{ \} \\\} \\ \\\\} $str] return "lappend _o \"$str\""
}
proc ::tmpl_parser::normal_parse {str} {
return "lappend _o $str"
}
proc ::tmpl_parser::numeric_parse {str} {
return "lappend _o [expr $str]"
}
[ Category Application | Category Template Category Template and Macro processing ]