regex101: PCRE (Legacy) Match Workspace

Regular Expression

(?P<rulename><\S+>)\s*::=\s*(?P<production>(?:(?=\#)\#[^\r\n]*|(?!<\S+>\s*::=).+?)+)

# *****************************************************************************
# Smallest grammar
# *****************************************************************************

# structure

<predefined> ::= 'b0 = b1 = b2 = bool()'
                 'i0 = i1 = i2 = int()'
                 'res = int()'
                 <code>

# *****************************************************************************
<bool_var> ::= 'b0' | 'b1' | 'b2'
<int_var> ::= 'i0' | 'i1' | 'i2' | 'in0' | 'in1' | 'in2' | 'in3' | 'res'
# *****************************************************************************

<code> ::= <code><code> | <statement>'\n'

<statement> ::= <assign> | <compound_stmt>
<compound_stmt> ::= <if> | <while>

            # from bool
<assign> ::= <bool_assign>
           # from int
           | <int_assign>

<if> ::= <if-then> | <if-then><else>

<if-then> ::= 'if '<bool><block>
<else> ::= 'else'<block>

<block> ::= ':{:\n'<code>':}'


<while> ::= <loop-header>'while '<bool><loop-block>

<loop-header> ::= 'loopBreak% = 0\n'
# stop[0] is set by outer code to break immediately
<loop-block> ::=':{:\n'<code>'\nif loopBreak% > loopBreakConst or stop[0]:{:\nbreak\n:}\nloopBreak% += 1:}'

# bool

<bool_assign> ::= <bool_var>' = '<bool>

<bool_var_const> ::= <bool_var> | <bool_const>

<bool> ::= <bool_var> | <bool_const>
         | <bool_pre> <bool_var_const>
         | '(' <bool_var_const> <bool_op> <bool_var_const> ')'
         # from int
         | <int> <comp_op> <int>

<bool_op> ::= 'and' | 'or'
<bool_pre> ::= 'not'

<bool_const> ::= 'True' | 'False'

# int

<int_assign> ::= <int_var> '=' <int> | <int_var> <arith_assign> <int>

<int_var_const> ::= <int_var> | <int_const>

<int> ::= <int_var> | <int_const>
        | <arith_prefix><int_var_const>
        | '(' <int_var_const> <arith_ops> <int_var_const> ')'
        | <int_arith_ops_protected>'('<int_var_const>','<int_var_const>')'
        | 'min('<int_var_const>', '<int_var_const>')'
        | 'max('<int_var_const>', '<int_var_const>')'
        | 'abs('<int_var_const>')'

# to avoid problems with leading zeros in python int
<int_const> ::= 'int('<number>'.0)'
<number> ::= <num> | <num><num> | <num><num><num> | <num><num><num><num> | <num><num><num><num><num>
           | <num><num><num><num><num><num> | <num><num><num><num><num><num><num>
           | <num><num><num><num><num><num><num><num> | <num><num><num><num><num><num><num><num><num>
           | <num><num><num><num><num><num><num><num><num><num>
<num> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9

<arith_assign> ::= <arith_ops>'='
<arith_ops> ::= '+'|'-'|'*'
# ** raises ZeroDivision error when 'a = 0; a ** ~a'
# |'**'

<int_arith_ops_protected> ::= 'divInt' | 'mod'
<arith_prefix> ::= '+'|'-'
#|'~'

<comp_op> ::= '<'|'>'|'=='|'>='|'<='|'!='|'is'|'is not'

Substitution

# *****************************************************************************
# Smallest grammar
# *****************************************************************************

# structure

<predefined> ::= 'b0 = b1 = b2 = bool()'
                 'i0 = i1 = i2 = int()'
                 'res = int()'
                 <code>

# *****************************************************************************
<bool_var> ::= 'b0' | 'b1' | 'b2'
<int_var> ::= 'i0' | 'i1' | 'i2' | 'in0' | 'in1' | 'in2' | 'in3' | 'res'
# *****************************************************************************

<code> ::= <code><code> | <statement>'\n'

<statement> ::= <assign> | <compound_stmt>
<compound_stmt> ::= <if> | <while>

            # from bool
<assign> ::= <bool_assign>
           # from int
           | <int_assign>

<if> ::= <if-then> | <if-then><else>

<if-then> ::= 'if '<bool><block>
<else> ::= 'else'<block>

<block> ::= ':{:\n'<code>':}'


<while> ::= <loop-header>'while '<bool><loop-block>

<loop-header> ::= 'loopBreak% = 0\n'
# stop[0] is set by outer code to break immediately
<loop-block> ::=':{:\n'<code>'\nif loopBreak% > loopBreakConst or stop[0]:{:\nbreak\n:}\nloopBreak% += 1:}'

# bool

<bool_assign> ::= <bool_var>' = '<bool>

<bool_var_const> ::= <bool_var> | <bool_const>

<bool> ::= <bool_var> | <bool_const>
         | <bool_pre> <bool_var_const>
         | '(' <bool_var_const> <bool_op> <bool_var_const> ')'
         # from int
         | <int> <comp_op> <int>

<bool_op> ::= 'and' | 'or'
<bool_pre> ::= 'not'

<bool_const> ::= 'True' | 'False'

# int

<int_assign> ::= <int_var> '=' <int> | <int_var> <arith_assign> <int>

<int_var_const> ::= <int_var> | <int_const>

<int> ::= <int_var> | <int_const>
        | <arith_prefix><int_var_const>
        | '(' <int_var_const> <arith_ops> <int_var_const> ')'
        | <int_arith_ops_protected>'('<int_var_const>','<int_var_const>')'
        | 'min('<int_var_const>', '<int_var_const>')'
        | 'max('<int_var_const>', '<int_var_const>')'
        | 'abs('<int_var_const>')'

# to avoid problems with leading zeros in python int
<int_const> ::= 'int('<number>'.0)'
<number> ::= <num> | <num><num> | <num><num><num> | <num><num><num><num> | <num><num><num><num><num>
           | <num><num><num><num><num><num> | <num><num><num><num><num><num><num>
           | <num><num><num><num><num><num><num><num> | <num><num><num><num><num><num><num><num><num>
           | <num><num><num><num><num><num><num><num><num><num>
<num> ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9

<arith_assign> ::= <arith_ops>'='
<arith_ops> ::= '+'|'-'|'*'
# ** raises ZeroDivision error when 'a = 0; a ** ~a'
# |'**'

<int_arith_ops_protected> ::= 'divInt' | 'mod'
<arith_prefix> ::= '+'|'-'
#|'~'

<comp_op> ::= '<'|'>'|'=='|'>='|'<='|'!='|'is'|'is not'