70 lines
1.5 KiB
Go
70 lines
1.5 KiB
Go
package saccharine
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import (
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"fmt"
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"strings"
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)
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func stringifyAtom(n *Variable) string {
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return n.Name
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}
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func stringifyAbstraction(n *Abstraction) string {
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return "\\" + strings.Join(n.Parameters, " ") + "." + Stringify(n.Body)
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}
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func stringifyApplication(n *Application) string {
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arguments := []string{Stringify(n.Abstraction)}
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for _, argument := range n.Arguments {
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arguments = append(arguments, Stringify(argument))
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}
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return "(" + strings.Join(arguments, " ") + ")"
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}
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func stringifyLet(s *LetStatement) string {
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return s.Name + " " + strings.Join(s.Parameters, " ") + " := " + Stringify(s.Body)
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}
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func stringifyDeclare(s *DeclareStatement) string {
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return Stringify(s.Value)
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}
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func stringifyStatement(s Statement) string {
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switch s := s.(type) {
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case *DeclareStatement:
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return stringifyDeclare(s)
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case *LetStatement:
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return stringifyLet(s)
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default:
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panic(fmt.Errorf("unknown statement type: %v", s))
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}
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}
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func stringifyClause(n *Clause) string {
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stmts := ""
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for _, statement := range n.Statements {
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stmts += stringifyStatement(statement) + "; "
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}
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return "{ " + stmts + Stringify(n.Returns) + " }"
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}
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// Convert an expression back into valid source code.
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func Stringify(n Expression) string {
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switch n := n.(type) {
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case *Variable:
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return stringifyAtom(n)
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case *Abstraction:
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return stringifyAbstraction(n)
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case *Application:
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return stringifyApplication(n)
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case *Clause:
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return stringifyClause(n)
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default:
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panic(fmt.Errorf("unknown expression type: %T", n))
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}
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}
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