dbohdan 2016-09-21: This is a simple
Tcl extension written in
Terra
, a new statically typed language related to and meta-programmed with
Lua. It is impressively easy to interface with C libraries.
This code has been tested with Terra release-2016-03-25 (
terra-Linux-x86_64-332a506). Compile and test using the command
terra tclterraexample.t \
&& gcc -fPIC tclterraexample.o -shared -o tclterraexample.so -ltclstub8.6 \
&& echo 'load tclterraexample.so; puts [hello]; puts [square 5]' | tclsh
tclterraexample.t edit
local tcl = terralib.includec("tcl.h")
-- Terra can't access the value of TCL_VERSION in tcl.h. It currently only
-- imports macros with definitions representable in the type double. We'll
-- define an equivalent constant instead.
local TCL_VERSION = constant(tcl.TCL_MAJOR_VERSION .. "." ..
tcl.TCL_MINOR_VERSION)
terra Hello_Cmd(cdata: tcl.ClientData, interp: &tcl.Tcl_Interp, objc: int,
objv: &&tcl.Tcl_Obj): int
if objc ~= 1 then
tcl.Tcl_WrongNumArgs(interp, 1, objv, nil)
return tcl.TCL_ERROR
end
tcl.Tcl_SetObjResult(interp, tcl.Tcl_NewStringObj("Hello, World!", -1))
return tcl.TCL_OK
end
terra Square_Cmd(cdata: tcl.ClientData, interp: &tcl.Tcl_Interp, objc: int,
objv: &&tcl.Tcl_Obj): int
if objc ~= 2 then
tcl.Tcl_WrongNumArgs(interp, 1, objv, "value")
return tcl.TCL_ERROR
end
var i: int = 0
if tcl.Tcl_GetIntFromObj(interp, objv[1], &i) ~= tcl.TCL_OK then
return tcl.TCL_ERROR
end
tcl.Tcl_SetObjResult(interp, tcl.Tcl_NewIntObj(i*i))
return tcl.TCL_OK
end
terra Tclterraexample_Init(interp: &tcl.Tcl_Interp): int
if tcl.Tcl_InitStubs(interp, TCL_VERSION, 0) == nil then
return tcl.TCL_ERROR;
end
tcl.Tcl_CreateObjCommand(interp, "::hello", Hello_Cmd, nil, nil)
tcl.Tcl_CreateObjCommand(interp, "::square", Square_Cmd, nil, nil)
return tcl.TCL_OK
end
terralib.saveobj("tclterraexample.o", {
Tclterraexample_Init = Tclterraexample_Init
})
