Packages

leibniz

1.0.0
1.0.0

Math expression parser and evaluator

HexDocs

Current section

Files

Jump to
Readme
1 Version
0 Dependencies
Dependants
Files
Activity
leibniz src lexer.xrl
Raw

src/lexer.xrl 

Definitions.



CHAR         = [a-z_]

ADD_OPERATOR = (\+|-)

MUL_OPERATOR = (\*|/)

POW_OPERATOR = \^

DIGIT        = [0-9]

OPEN_PAREN   = \(

CLOSE_PAREN  = \)

WHITE        = [\s|\t]



Rules.



{CHAR}+             : {token, {identifier, TokenLine, list_to_atom(TokenChars)}}.

{ADD_OPERATOR}      : {token, {add_operator, TokenLine, list_to_atom(TokenChars)}}.

{MUL_OPERATOR}      : {token, {mul_operator, TokenLine, list_to_atom(TokenChars)}}.

{POW_OPERATOR}      : {token, {pow_operator, TokenLine, list_to_atom(TokenChars)}}.

{DIGIT}+            : {token, {int, TokenLine, list_to_integer(TokenChars)}}.

{DIGIT}+\.{DIGIT}+  : {token, {float, TokenLine, list_to_float(TokenChars)}}.

{OPEN_PAREN}        : {token, {open_paren, TokenLine, list_to_atom(TokenChars)}}.

{CLOSE_PAREN}       : {token, {close_paren, TokenLine, list_to_atom(TokenChars)}}.

{WHITE}+            : skip_token.





Erlang code.