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tanszek:oktatas:techcomm:bn_formulas

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tanszek:oktatas:techcomm:bn_formulas [2024/10/07 16:22] – created kneheztanszek:oktatas:techcomm:bn_formulas [2024/10/07 16:33] (current) knehez
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 Syntax definition: Syntax definition:
 $$ $$
-<license\_plate>::<newType> | <oldType> \\ +<license\_plate>::=<newType> | <oldType> \\ 
-<oldType>::={<letter>}_3^3 − {<number>}_3^3 \\ +<oldType>::=\{<letter>\}_3^3 − \{<number>\}_3^3 \\ 
-<newType>::={<letter>}_2^2 − {<letter>}_2^2 − {<number>}_3^3 \\+<newType>::=\{<letter>\}_2^2 − \{<letter>\}_2^2 − \{<number>\}_3^3 \\
 <letter>::=A|B|C...|Z \\ <letter>::=A|B|C...|Z \\
 <number>::=0|1|2|3|4|5|6|7|8|9 \\ <number>::=0|1|2|3|4|5|6|7|8|9 \\
Line 32: Line 32:
  
 ''062012345, +36301234567, 0680460046'' ''062012345, +36301234567, 0680460046''
 +
 +Syntax definition:
 +$$
 +<phone call>::= \{<prefix>\}_0^1 <city> <customer> \\
 +<prefix>::=\{+\}_0^1 36|06 \\
 +<city>::=\{<number>\}_1^2\\
 +<customer>::=\{<number>\}_6^7\\
 +<number>::=0|1|2|3|4|5|6|7|8|9 \\
 +$$
 +
 +=== 3. Example: How can we describe the BNF formula using itself? ===
 +
 +\[
 +\langle \text{BN formula} \rangle ::= \langle \text{rule} \rangle 
 +\]
 +\[
 +\langle \text{rule} \rangle ::= \langle \text{identifier} \rangle "::=" \langle \text{expression} \rangle
 +\]
 +\[
 +\langle \text{identifier} \rangle ::= "\langle" \langle \text{letter} \rangle \mid \left\lbrace \langle \text{letter} \rangle \mid \langle \text{digit} \rangle \right\rbrace "\rangle"
 +\]
 +\[
 +\langle \text{expression} \rangle ::= \langle \text{term} \rangle \left\lbrace "|" \langle \text{term} \rangle \right\rbrace
 +\]
 +\[
 +\langle \text{term} \rangle ::= \langle \text{factor} \rangle \left\lbrace \langle \text{factor} \rangle \right\rbrace
 +\]
 +\[
 +\langle \text{factor} \rangle ::= \langle \text{identifier} \rangle \mid \langle \text{terminal\_symbol} \rangle
 +\]
 +\[
 +\langle \text{terminal\_symbol} \rangle ::= \left\lbrace \langle \text{character} \rangle \right\rbrace
 +\]
 +\[
 +\langle \text{letter} \rangle ::= \langle \text{uppercase} \rangle \mid \langle \text{lowercase} \rangle
 +\]
 +\[
 +\langle \text{uppercase} \rangle ::= A \mid B \mid C \dots Z
 +\]
 +\[
 +\langle \text{lowercase} \rangle ::= a \mid b \mid c \dots z
 +\]
 +\[
 +\langle \text{digit} \rangle ::= 0 \mid 1 \mid 2 \mid 3 \mid 4 \mid 5 \mid 6 \mid 7 \mid 8 \mid 9
 +\]
 +
 +
tanszek/oktatas/techcomm/bn_formulas.1728318130.txt.gz · Last modified: 2024/10/07 16:22 by knehez