EBNF Grammar

maxtypeProgram       = { function_declaration | statement | function_call | variable_declaration } ;

function_declaration = 'fun' ID '(' parameter_list '):' block ;

variable_declaration = 'type' ID ':' type [ '=' expression ] ';' ;

parameter_list       = parameter { ',' parameter } ;

parameter            = ID ':' type ;

type                 = 'number' | 'boolean' | 'string' ;

block                = '{' statement* '}' ;

statement            = assignment
                      | function_call
                      | if_statement
                      | while_statement
                      | return_statement ;

assignment           = ID '=' expression ';' ;

function_call        = ID '(' argument_list ')' ';' ;

argument_list        = expression { ',' expression } ;

if_statement         = 'if' '[' expression ']' ':' block
                        { 'elif' '[' expression ']' ':' block }
                        [ 'else' ':' block ] ;

while_statement      = 'while' '[' expression ']' ':' block ;

return_statement     = 'return' expression ';' ;

expression           = logical_or ;

logical_or           = logical_and { 'or' logical_and } ;

logical_and          = equality { 'and' equality } ;

equality             = relational [ ( '==' | '!=' ) relational ] ;

relational           = additive [ ( '<' | '>' | '<=' | '>=' ) additive ] ;

additive             = multiplicative { ( '+' | '-' ) multiplicative } ;

multiplicative       = unary { ( '*' | '/' | '%' ) unary } ;

unary                = [ '-' | 'not' ] primary ;

primary              = '(' expression ')'
                      | ID
                      | NUMBER
                      | STRING
                      | BOOLEAN ;

ID                   = [a-zA-Z_][a-zA-Z0-9_]* ;
NUMBER               = [0-9]+ ;
STRING               = '"' .*? '"' ;
BOOLEAN              = 'true' | 'false' ;

WS                   = [ \t\r\n]+ ;