36 lines
807 B
Go
36 lines
807 B
Go
package config
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import (
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"flag"
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"fmt"
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)
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// Extract the program configuration from the command-line arguments.
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func FromArgs() (*Config, error) {
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// Parse flags.
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verbose := flag.Bool("v", false, "Verbosity. If set, the program will print logs.")
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explanation := flag.Bool("x", false, "Explanation. Whether or not to show all reduction steps.")
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flag.Parse()
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// Parse non-flag arguments.
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if flag.NArg() == 0 {
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return nil, fmt.Errorf("no input given")
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} else if flag.NArg() > 1 {
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return nil, fmt.Errorf("more than 1 command-line argument")
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}
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// Parse source type.
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var source Source
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if flag.Arg(0) == "-" {
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source = StdinSource{}
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} else {
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source = StringSource{data: flag.Arg(0)}
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}
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return &Config{
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Source: source,
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Verbose: *verbose,
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Explanation: *explanation,
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}, nil
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}
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