salix/include_tag.go

74 lines
2.0 KiB
Go

/*
* Salix - Go templating engine
* Copyright (C) 2023 Elara Musayelyan
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package salix
import (
"errors"
"go.elara.ws/salix/ast"
)
var (
ErrIncludeInvalidArgs = errors.New("include expects one string argument")
ErrNoSuchTemplate = errors.New("no such template")
)
// includeTag represents an #include tag within a Salix template
type includeTag struct{}
func (it includeTag) Run(tc *TagContext, block, args []ast.Node) error {
if len(args) < 1 {
return tc.PosError(tc.Tag, "expected at least one argument, got %d", len(args))
}
val, err := tc.GetValue(args[0], nil)
if err != nil {
return err
}
name, ok := val.(string)
if !ok {
return tc.PosError(args[0], "invalid first argument type: %T (expected string)", val)
}
tmpl, ok := tc.t.ns.GetTemplate(name)
if !ok {
return tc.PosError(args[0], "no such template: %q", name)
}
local := map[string]any{}
// Use the variable assignments after the first argument
// to set the local variables of the execution
for _, arg := range args[1:] {
if a, ok := arg.(ast.Assignment); ok {
val, err := tc.GetValue(a.Value, local)
if err != nil {
return err
}
local[a.Name.Value] = val
} else {
// If the argument isn't an assigment, return an error
return tc.PosError(tc.Tag, "invalid argument type: %T (expected ast.Assignment)", val)
}
}
return tc.Execute(tmpl.ast, local)
}