| author | Oleksandr Gavenko <gavenkoa@gmail.com> |
| Sat, 10 Feb 2018 01:36:16 +0200 | |
| changeset 2229 | 1a0b6597e594 |
| parent 2228 | 837f1337c59b |
| permissions | -rw-r--r-- |
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1905
fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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.. -*- coding: utf-8; -*- |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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===== |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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BNF |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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===== |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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What is BNF? |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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============ |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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.. contents:: |
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Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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:local: |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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BNF is an acronym for "Backus Naur Form". John Backus and Peter Naur introduced |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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for the first time a formal notation to describe the syntax of a given language |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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(ALGOL 60 programming language). |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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changeset
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See: :rfc:`2234`. |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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BNF syntax |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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========== |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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The meta-symbols of BNF are: |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
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``::=`` |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
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Meaning "is defined as". |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
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``|`` |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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Meaning "or". |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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``<``, ``>`` |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
28 |
Angle brackets used to surround category names (some times skipped). |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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``[``, ``]`` |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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Optional items are enclosed in. |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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``{``, ``}``
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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Repetitive items (zero or more times) are enclosed in. |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
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``"abc..."`` |
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837f1337c59b
Removed indentation that compiled into <blockquote>.
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
1912
diff
changeset
|
34 |
Terminals are enclosed in to distinguish them from meta-symbols. |
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1905
fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
|
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
|
36 |
BNF in BNF |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
|
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========== |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
|
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:: |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
|
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syntax ::= { rule }
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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rule ::= identifier "::=" expression |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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expression ::= term { "|" term }
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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term ::= factor { factor }
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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factor ::= identifier | |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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quoted_symbol | |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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"(" expression ")" |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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"[" expression "]" | |
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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"{" expression "}"
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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identifier ::= letter { letter | digit }
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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quoted_symbol ::= """ { any_character } """
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fba288d59662
Include only local subsections into TOC. This prevent duplication of
Oleksandr Gavenko <gavenkoa@gmail.com>
parents:
diff
changeset
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