Copyright (c) 2009 The Go Authors. All rights reserved.

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modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
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   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer

Copyright (c) 2012 The Go Authors. All rights reserved.

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modification, are permitted provided that the following conditions are
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   * Redistributions of source code must retain the above copyright
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Copyright ©2013 The gonum Authors. All rights reserved.

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    * Redistributions of source code must retain the above copyright
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// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package lex

import (
	"text/scanner"

	"cmd/internal/src"
)

// A Stack is a stack of TokenReaders. As the top TokenReader hits EOF,
// it resumes reading the next one down.
type Stack struct {
	tr []TokenReader
}

Copyright (c) 2012-2023 The ANTLR Project. All rights reserved.

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modification, are permitted provided that the following conditions
are met:

1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright

Copyright 2013 ChaiShushan <chaishushan{AT}gmail.com>. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above

Copyright (c) 2012 The Go Authors. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer

Copyright (c) 2017 The Go Authors. All rights reserved.

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modification, are permitted provided that the following conditions are
met:

   * Redistributions of source code must retain the above copyright
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   * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer

Copyright (c) 2023 The Gorilla Authors. All rights reserved.

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modification, are permitted provided that the following conditions are
met:

	 * Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
	 * Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer

Copyright (c) 2015, Gengo, Inc.
All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright notice,