53 lines
1005 B
Go
53 lines
1005 B
Go
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package vm
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import (
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"context"
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"fmt"
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"regexp"
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"git.defalsify.org/festive/state"
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)
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var (
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inputRegexStr = "^[a-zA-Z0-9].*$"
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inputRegex = regexp.MustCompile(inputRegexStr)
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ctrlInputRegexStr = "^[<>_]$"
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ctrlInputRegex = regexp.MustCompile(inputRegexStr)
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)
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func CheckInput(input []byte) error {
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if !inputRegex.Match(input) {
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return fmt.Errorf("Input '%s' does not match format /%s/", input, inputRegexStr)
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}
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return nil
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}
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func applyControlInput(input []byte, st *state.State, ctx context.Context) (string, error) {
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var err error
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sym, idx := st.Where()
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switch input[0] {
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case '_':
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sym, err = st.Up()
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if err != nil {
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return sym, err
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}
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}
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_ = idx
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return sym, nil
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}
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func ApplyInput(inputString string, st *state.State, ctx context.Context) (string, error) {
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input := []byte(inputString)
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if ctrlInputRegex.Match(input) {
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return applyControlInput(input, st, ctx)
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}
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err := CheckInput(input)
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if err != nil {
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return "", err
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}
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st.Down(inputString)
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return inputString, nil
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}
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