Skip to content

Instantly share code, notes, and snippets.

@srenatus
Created June 16, 2023 13:39
Show Gist options
  • Save srenatus/5361bfa8c4044aad97fa62af27d5bbcb to your computer and use it in GitHub Desktop.
Save srenatus/5361bfa8c4044aad97fa62af27d5bbcb to your computer and use it in GitHub Desktop.
diff --git a/topdown/arithmetic.go b/topdown/arithmetic.go
index c75f816a4..b0061074f 100644
--- a/topdown/arithmetic.go
+++ b/topdown/arithmetic.go
@@ -6,6 +6,7 @@ package topdown
import (
"math/big"
+ "strconv"
"fmt"
@@ -113,6 +114,42 @@ func builtinArithArity2(fn arithArity2) BuiltinFunc {
}
}
+var Ints map[string]int
+var Snti map[int]string
+
+func init() {
+ Ints = make(map[string]int, 256)
+ Snti = make(map[int]string, 256)
+ for i := 0; i < 256; i++ {
+ j := strconv.Itoa(i)
+ Ints[j] = i
+ Snti[i] = j
+ }
+}
+
+func builtinArithPlus(_ BuiltinContext, operands []*ast.Term, iter func(*ast.Term) error) error {
+ n1, err := builtins.NumberOperand(operands[0].Value, 1)
+ if err != nil {
+ return err
+ }
+ n2, err := builtins.NumberOperand(operands[1].Value, 2)
+ if err != nil {
+ return err
+ }
+ if f, ok := Ints[string(n1)]; ok {
+ if g, ok := Ints[string(n2)]; ok {
+ if h, ok := Snti[f+g]; ok {
+ return iter(ast.NewTerm(ast.Number(h)))
+ }
+ }
+ }
+ f, err := arithPlus(builtins.NumberToFloat(n1), builtins.NumberToFloat(n2))
+ if err != nil {
+ return err
+ }
+ return iter(ast.NewTerm(builtins.FloatToNumber(f)))
+}
+
func builtinMinus(_ BuiltinContext, operands []*ast.Term, iter func(*ast.Term) error) error {
n1, ok1 := operands[0].Value.(ast.Number)
@@ -176,7 +213,7 @@ func init() {
RegisterBuiltinFunc(ast.Round.Name, builtinArithArity1(arithRound))
RegisterBuiltinFunc(ast.Ceil.Name, builtinArithArity1(arithCeil))
RegisterBuiltinFunc(ast.Floor.Name, builtinArithArity1(arithFloor))
- RegisterBuiltinFunc(ast.Plus.Name, builtinArithArity2(arithPlus))
+ RegisterBuiltinFunc(ast.Plus.Name, builtinArithPlus)
RegisterBuiltinFunc(ast.Minus.Name, builtinMinus)
RegisterBuiltinFunc(ast.Multiply.Name, builtinArithArity2(arithMultiply))
RegisterBuiltinFunc(ast.Divide.Name, builtinArithArity2(arithDivide))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment