expr/operand-expr.go

31 lines
673 B
Go

// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.
// operand-expr.go
package expr
import "fmt"
// -------- expr term
func newExprTerm(root *term) *term {
tk := NewValueToken(root.tk.row, root.tk.col, SymExpression, root.source(), root)
return &term{
tk: *tk,
parent: nil,
children: nil,
position: posLeaf,
priority: priValue,
evalFunc: evalExpr,
}
}
// -------- eval expr
func evalExpr(ctx ExprContext, opTerm *term) (v any, err error) {
if expr, ok := opTerm.value().(*term); ok {
v, err = expr.compute(ctx)
} else {
err = fmt.Errorf("expression expected, got %T", opTerm.value())
}
return
}