92 lines
3.9 KiB
C++
92 lines
3.9 KiB
C++
/*
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<>术语符号
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|并列选项，只能选一个
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*/
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//basic elements
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<identifier> ::= IDENTIFIER
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<number> ::= NUMBER
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<string> ::= STRING
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//scalar
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<identifier> ::= <identifier>|<array_search>|<hash_search>
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<identifiers> ::= <identifier> <,> <identifier>
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<identifiers> ::= <identifiers> <,> <identifier>
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<scalar> ::= <number>|<string>|<array>|<hash>|<use_function>
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<scalars> ::= <scalar> <,> <scalar>
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<scalars> ::= <scalars> <,> <scalar>
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//array
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<array_search> ::= <identifier> <[> <number> <]>
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<array> ::= <[> <scalar>|<scalars>|<identifier>|<identifiers> <]>
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//hash
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<hash_search> ::= <identifier> <.> <identifier>|<use_function>
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<hash_member> ::= <identifier> <:> <identifier>|<scalar>|<function>
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<hash_members> ::= <hash_member> <,> <hash_member>
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<hash_members> ::= <hash_members> <,> <hash_member>
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<hash> ::= <{> <hash_member>|<hash_members> <}>
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//function
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<function> ::= <func> <(> <identifier>|<identifiers> <)> <{> <statement>|<statements> <}>
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<use_function> ::= <use_identifier> <(> <scalar>|<scalars>|<identifier>|<identifiers> <)>
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//definition & assignment
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<definition> ::= <var> <identifier> <=> <scalar>|<identifier>|<function> <;>
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<assignment> ::= <identifier> <=>|<+=>|<-=>|<*=>|</=>|<~=> <scalar>|<identifier> <;>
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//calculation
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<add> ::= <scalar>|<identifier> <+> <scalar>|<identifier>
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<sub> ::= <scalar>|<identifier> <-> <scalar>|<identifier>
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<mul> ::= <scalar>|<identifier> <*> <scalar>|<identifier>
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<div> ::= <scalar>|<identifier> </> <scalar>|<identifier>
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<link> ::= <scalar>|<identifier> <~> <scalar>|<identifier>
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<calc> ::= <add>|<sub>|<mul>|<div>
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<calcs> ::= <(> <calc>|<calcs> <)>
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<calcs> ::= <calc> <+>|<->|<*>|</>|<~> <calc>
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<calcs> ::= <calcs> <+>|<->|<*>|</>|<~> <calc>
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<calcs> ::= <calc> <+>|<->|<*>|</>|<~> <calcs>
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//loop
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<loop_condition> ::= <statement>|<statements> <;> <condition>|<conditions> <;> <statement>|<statements>
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<loop> ::= <for> <(> <loop_condition> <)> <statement>|<{> <statement>|<statements> <}>
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<loop> ::= <while> <(> <condition>|<conditions> <)> <statement>|<{> <statement>|<statements> <}>
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//if else
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<condition_link_operator> ::= <and>|<or>|<!>
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<cmp_operator> ::= <==>|<>>|<<>|<<=>|<>=>|<!=>|<condition_link_operator>
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<condition> ::= <scalar>|<identifier>
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<condition> ::= <scalar>|<identifier> <cmp_operator> <scalar>|<identifier>
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<conditions> ::= <(> <condition> <)> <condition_link_operator> <(> <condition> <)>
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<conditions> ::= <(> <conditions> <)> <condition_link_operator> <(> <condition> <)>
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<conditions> ::= <(> <condition> <)> <condition_link_operator> <(> <conditions> <)>
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<conditions> ::= <conditions> <condition_link_operator> <(> <condition> <)>
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<conditions> ::= <conditions> <condition_link_operator> <(> <conditions> <)>
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//(e==1) && (e==2)
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//((e==1) && (e==2)) && (e==3)
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//(e==1) && ((e==2) && (e==3))
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//(e==1) && (e==2) && (e==3) && ((e==4) && (e==5))
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<_if> ::= <if> <(> <condition>|<conditions> <)> <statement>
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<_if> ::= <if> <(> <condition>|<conditions> <)> <{> <statement>|<statements> <}>
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<_else> ::= <else> <statement>
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<_else> ::= <else> <{> <statement>|<statements> <}>
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<else_if> ::= <else> <if> <(> <condition>|<conditions> <)> <statement>
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<else_if> ::= <else> <if> <(> <condition>|<conditions> <)> <{> <statement>|<statements> <}>
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<else_ifs> ::= <else_if> <else_if>
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<else_ifs> ::= <else_ifs> <else_if>
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<choose> ::= <_if>
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<choose> ::= <_if> <_else>
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<choose> ::= <_if> <else_if>
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<choose> ::= <_if> <else_ifs>
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<choose> ::= <_if> <else_if> <_else>
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<choose> ::= <_if> <else_ifs> <_else>
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//statement
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<func_return> ::= <return> <scalar>|<identifier> <;>
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<loop_continue> ::= <continue> <;>
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<loop_break> ::= <break> <;>
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<print_function> ::= <print> <(> <scalar>|<scalars>|<identifier>|<identifiers> <)> <;>
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<statement> ::= <definition>|<assignment>|<loop>|<choose>|<use_function>|<func_return>|<loop_continue>|<loop_break>|<print_function>
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<statements> ::= <statement> <statement>
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<statements> ::= <statements> <statement>
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