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Fix typos in the documentation of Parser/pgen (GH-15416)

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Co-Authored-By: Antoine <43954001+awecx@users.noreply.github.com>
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Shashi Ranjan 2019-08-24 23:37:24 +05:30 committed by Pablo Galindo
parent 8ad22a4226
commit 43710b67b3
1 changed files with 7 additions and 7 deletions
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14
Parser/pgen/pgen.py
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@ -10,11 +10,11 @@
* An LL(1) parser (Left-to-right, Leftmost derivation, 1 token-lookahead) is a
top-down parser for a subset of context-free languages. It parses the input
from Left to right, performing Leftmost derivation of the sentence, and can
only use 1 tokens of lookahead when parsing a sentence.
only use 1 token of lookahead when parsing a sentence.
* A parsing table is a collection of data that a generic implementation of the
LL(1) parser consumes to know how to parse a given context-free grammar. In
this case the collection of thata involves Deterministic Finite Automatons,
this case the collection of data involves Deterministic Finite Automatons,
calculated first sets, keywords and transition labels.
* A grammar is defined by production rules (or just 'productions') that specify
@ -26,9 +26,9 @@
rule_name: rule_description;
meaning the rule 'a: b' specifies that a can be replaced by b. A Context-free
grammars is a grammars in which the left-hand side of each production rule
consists of only a single nonterminal symbol. Context free grammars can
meaning the rule 'a: b' specifies that a can be replaced by b. A context-free
grammar is a grammar in which the left-hand side of each production rule
consists of only a single nonterminal symbol. Context-free grammars can
always be recognized by a Non-Deterministic Automatons.
* Terminal symbols are literal symbols which may appear in the outputs of the
@ -47,8 +47,8 @@
* The first sets of a rule (FIRST(rule)) are defined to be the set of terminals
that can appear in the first position of any string derived from the rule.
This is useful for LL(1) parsers as the parser is only allow to look at the
next token in the input to know which rule needs to parse. For example given
This is useful for LL(1) parsers as the parser is only allowed to look at the
next token in the input to know which rule needs to parse. For example, given
this grammar:
start: '(' A | B ')'