q/src/build/ast/parseNode.go

43 lines
1000 B
Go

package ast
import (
"git.akyoto.dev/cli/q/src/build/errors"
"git.akyoto.dev/cli/q/src/build/expression"
"git.akyoto.dev/cli/q/src/build/token"
)
// parseNode generates an AST node from an instruction.
func parseNode(tokens token.List, source []byte, nodes AST) (Node, error) {
if tokens[0].IsKeyword() {
return parseKeyword(tokens, source, nodes)
}
expr := expression.Parse(tokens)
if expr == nil {
return nil, nil
}
switch {
case IsVariableDefinition(expr):
if len(expr.Children) < 2 {
return nil, errors.New(errors.MissingOperand, nil, expr.Token.End())
}
return &Define{Expression: expr}, nil
case IsAssignment(expr):
if len(expr.Children) < 2 {
return nil, errors.New(errors.MissingOperand, nil, expr.Token.End())
}
return &Assign{Expression: expr}, nil
case IsFunctionCall(expr):
return &Call{Expression: expr}, nil
default:
return nil, errors.New(&errors.InvalidInstruction{Instruction: expr.Token.Text(source)}, nil, expr.Token.Position)
}
}