Preprocessor
_Preprocessor of DSL code
This contract is a singleton and should not be deployed more than once
It can remove comments that were created by user in the DSL code string. It
transforms the users DSL code string to the list of commands that can be used
in a Parser contract.
DSL code in postfix notation as
user's string code -> Preprocessor -> each command is separated in the commands list_
function transform(address _ctxAddr, string _program) external view returns (string[] code)
_The main function that transforms the user's DSL code string to the list of commands.
Example:
The user's DSL code string is
uint256 6 setUint256 A
The end result after executing a transform() function is
['uint256', '6', 'setUint256', 'A']
```_
#### Parameters
| Name | Type | Description |
| ---- | ---- | ----------- |
| _ctxAddr | address | is a context contract address |
| _program | string | is a user's DSL code string |
#### Return Values
| Name | Type | Description |
| ---- | ---- | ----------- |
| code | string[] | The list of commands that storing `result` |
### removeComments
```solidity
function removeComments(string _program) public pure returns (string _cleanedProgram)
_Searches the comments in the program and removes comment lines
Example:
The user's DSL code string is
bool true
// uint256 2 * uint256 5
The end result after executing a removeComments() function is
bool true
```_
#### Parameters
| Name | Type | Description |
| ---- | ---- | ----------- |
| _program | string | is a current program string |
#### Return Values
| Name | Type | Description |
| ---- | ---- | ----------- |
| _cleanedProgram | string | new string program that contains only clean code without comments |
### split
```solidity
function split(string _program, string _separators, string _separatorsToKeep) public pure returns (string[])
_Splits the user's DSL code string to the list of commands
avoiding several symbols:
- removes additional and useless symbols as ' ', \\n
- defines and adding help 'end' symbol for the ifelse condition
- defines and cleans the code from { and } symbols
Example:
The user's DSL code string is
(var TIMESTAMP > var INIT)
The end result after executing a split() function is
['var', 'TIMESTAMP', '>', 'var', 'INIT']
```_
#### Parameters
| Name | Type | Description |
| ---- | ---- | ----------- |
| _program | string | is a user's DSL code string |
| _separators | string | Separators that will be used to split the string |
| _separatorsToKeep | string | we're using symbols from this string as separators but not removing them from the resulting array |
#### Return Values
| Name | Type | Description |
| ---- | ---- | ----------- |
| [0] | string[] | The list of commands that storing in `result` |
### removeSyntacticSugar
```solidity
function removeSyntacticSugar(string[] _code) public pure returns (string[])
Removes scientific notation from numbers and removes currency symbols
Example
1e3 = 1,000
1 GWEI = 1,000,000,000
1 ETH = 1,000,000,000,000,000,000
Parameters
| Name |
Type |
Description |
| _code |
string[] |
Array of DSL commands |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Code without syntactic sugar |
simplifyCode
function simplifyCode(string[] _code, address _ctxAddr) public view returns (string[])
Depending on the type of the command it gets simplified
Parameters
| Name |
Type |
Description |
| _code |
string[] |
Array of DSL commands |
| _ctxAddr |
address |
Context contract address |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Simplified code |
infixToPostfix
function infixToPostfix(address _ctxAddr, string[] _code) public view returns (string[])
Transforms code in infix format to the postfix format
Parameters
| Name |
Type |
Description |
| _ctxAddr |
address |
Context contract address |
| _code |
string[] |
Array of DSL commands |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Code in the postfix format |
_processArrayInsert
function _processArrayInsert(string[] _result, uint256 _resultCtr, string[] _code, uint256 i) internal pure returns (string[], uint256, uint256)
Process insert into array command
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _code |
string[] |
Current DSL code that we're processing |
| i |
uint256 |
Current pointer to the element in _code array that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
| [2] |
uint256 |
|
_processSumOfCmd
function _processSumOfCmd(string[] _result, uint256 _resultCtr, string[] _code, uint256 i) internal pure returns (string[], uint256, uint256)
Process summing over array comand
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _code |
string[] |
Current DSL code that we're processing |
| i |
uint256 |
Current pointer to the element in _code array that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
| [2] |
uint256 |
|
_processForCmd
function _processForCmd(string[] _result, uint256 _resultCtr, string[] _code, uint256 i) internal pure returns (string[], uint256, uint256)
Process for-loop
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _code |
string[] |
Current DSL code that we're processing |
| i |
uint256 |
Current pointer to the element in _code array that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
| [2] |
uint256 |
|
_processStruct
function _processStruct(string[] _result, uint256 _resultCtr, string[] _code, uint256 i) internal pure returns (string[], uint256, uint256)
Process struct comand
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _code |
string[] |
Current DSL code that we're processing |
| i |
uint256 |
Current pointer to the element in _code array that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
| [2] |
uint256 |
|
_processCurrencySymbol
function _processCurrencySymbol(uint256 _resultCtr, string _chunk, string _prevChunk) internal pure returns (uint256, string)
Process ETH, WEI symbols in the code
Parameters
| Name |
Type |
Description |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _chunk |
string |
The current piece of code that we're processing (should be the currency symbol) |
| _prevChunk |
string |
The previous piece of code |
Return Values
| Name |
Type |
Description |
| [0] |
uint256 |
Mofified _resultCtr, and modified _prevChunk |
| [1] |
string |
|
_processAlias
function _processAlias(string[] _result, uint256 _resultCtr, address _ctxAddr, string _chunk) internal view returns (string[], uint256)
Process DSL alias
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _ctxAddr |
address |
Context contract address |
| _chunk |
string |
The current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
_processCommand
function _processCommand(string[] _result, uint256 _resultCtr, string[] _code, uint256 i, address _ctxAddr) internal view returns (string[], uint256, uint256)
Process any DSL command
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _code |
string[] |
Current DSL code that we're processing |
| i |
uint256 |
Current pointer to the element in _code array that we're processing |
| _ctxAddr |
address |
Context contract address |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified i |
| [1] |
uint256 |
|
| [2] |
uint256 |
|
_processParenthesis
function _processParenthesis(string[] _stack, string[] _result, uint256 _resultCtr, string _chunk) internal pure returns (string[], uint256, string[])
Process open and closed parenthesis
Parameters
| Name |
Type |
Description |
| _stack |
string[] |
Stack that is used to process parenthesis |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _chunk |
string |
The current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified _stack |
| [1] |
uint256 |
|
| [2] |
string[] |
|
_processClosingParenthesis
function _processClosingParenthesis(string[] _stack, string[] _result, uint256 _resultCtr) public pure returns (string[], uint256, string[])
Process closing parenthesis
Parameters
| Name |
Type |
Description |
| _stack |
string[] |
Stack that is used to process parenthesis |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified _stack |
| [1] |
uint256 |
|
| [2] |
string[] |
|
_processCurlyBracket
function _processCurlyBracket(string[] _result, uint256 _resultCtr, string _chunk) internal pure returns (string[], uint256)
Process curly brackets
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _chunk |
string |
The current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr |
| [1] |
uint256 |
|
_processOperator
function _processOperator(string[] _stack, string[] _result, uint256 _resultCtr, address _ctxAddr, string _chunk) internal view returns (string[], uint256, string[])
Process any operator in DSL
Parameters
| Name |
Type |
Description |
| _stack |
string[] |
Stack that is used to process parenthesis |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _ctxAddr |
address |
Context contract address |
| _chunk |
string |
The current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr, and modified _stack |
| [1] |
uint256 |
|
| [2] |
string[] |
|
_isCurrencySymbol
function _isCurrencySymbol(string _chunk) internal pure returns (bool)
Checks if chunk is a currency symbol
Parameters
| Name |
Type |
Description |
| _chunk |
string |
is a current chunk from the DSL string code |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True or false based on whether chunk is a currency symbol or not |
_isOperator
function _isOperator(string _chunk, address _ctxAddr) internal view returns (bool)
Checks if chunk is an operator
Parameters
| Name |
Type |
Description |
| _chunk |
string |
|
| _ctxAddr |
address |
Context contract address |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True or false based on whether chunk is an operator or not |
_isAlias
function _isAlias(string _chunk, address _ctxAddr) internal view returns (bool)
Checks if a string is an alias to a command from DSL
Parameters
| Name |
Type |
Description |
| _chunk |
string |
|
| _ctxAddr |
address |
Context contract address |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True or false based on whether chunk is an alias or not |
_isParenthesis
function _isParenthesis(string _chunk) internal pure returns (bool)
Checks if chunk is a parenthesis
Parameters
| Name |
Type |
Description |
| _chunk |
string |
Current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True or false based on whether chunk is a parenthesis or not |
_isCurlyBracket
function _isCurlyBracket(string _chunk) internal pure returns (bool)
Checks if chunk is a curly bracket
Parameters
| Name |
Type |
Description |
| _chunk |
string |
Current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True or false based on whether chunk is a curly bracket or not |
_checkScientificNotation
function _checkScientificNotation(string _chunk) internal pure returns (string)
Parses scientific notation in the chunk if there is any
Parameters
| Name |
Type |
Description |
| _chunk |
string |
Current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string |
Chunk without a scientific notation |
_parseScientificNotation
function _parseScientificNotation(string _chunk) internal pure returns (string updatedChunk)
As the string of values can be simple and complex for DSL this function returns a number in
Wei regardless of what type of number parameter was provided by the user.
For example:
uint256 1000000 - simple
uint256 1e6 - complex
Parameters
| Name |
Type |
Description |
| _chunk |
string |
provided number |
Return Values
| Name |
Type |
Description |
| updatedChunk |
string |
amount in Wei of provided _chunk value |
_checkIsNumberOrAddress
function _checkIsNumberOrAddress(string[] _result, uint256 _resultCtr, string _chunk) internal pure returns (string[], uint256)
Checks if chunk is a number or address and processes it if so
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
| _chunk |
string |
Current piece of code that we're processing |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr |
| [1] |
uint256 |
|
_addUint256
function _addUint256(string[] _result, uint256 _resultCtr) internal pure returns (string[], uint256)
Adds uint256 to a number
Parameters
| Name |
Type |
Description |
| _result |
string[] |
Output array that the function is modifying |
| _resultCtr |
uint256 |
Current pointer to the empty element in the _result param |
Return Values
| Name |
Type |
Description |
| [0] |
string[] |
Modified _result array, mofified _resultCtr |
| [1] |
uint256 |
|
_getCurrencyMultiplier
function _getCurrencyMultiplier(string _chunk) internal pure returns (uint256)
checks the value, and returns the corresponding multiplier.
If it is Ether, then it returns 1000000000000000000,
If it is GWEI, then it returns 1000000000
Parameters
| Name |
Type |
Description |
| _chunk |
string |
is a command from DSL command list |
Return Values
| Name |
Type |
Description |
| [0] |
uint256 |
returns the corresponding multiplier. |
function _getCommentSymbol(uint256 i, string _program, string _char) internal pure returns (uint256, uint256, bool)
Checks if a symbol is a comment, then increases i to the next
no-comment symbol avoiding an additional iteration
Parameters
| Name |
Type |
Description |
| i |
uint256 |
is a current index of a char that might be changed |
| _program |
string |
is a current program string |
| _char |
string |
Current character |
Return Values
| Name |
Type |
Description |
| [0] |
uint256 |
Searched symbol length |
| [1] |
uint256 |
New index |
| [2] |
bool |
Is code commented or not |
function _getEndCommentSymbol(uint256 _ssl, uint256 i, string _p, string _char) internal pure returns (uint256, bool)
Checks if a symbol is an end symbol of a comment, then increases _index to the next
no-comment symbol avoiding an additional iteration
Parameters
| Name |
Type |
Description |
| _ssl |
uint256 |
is a searched symbol len that might be 0, 1, 2 |
| i |
uint256 |
is a current index of a char that might be changed |
| _p |
string |
is a current program string |
| _char |
string |
Current character |
Return Values
| Name |
Type |
Description |
| [0] |
uint256 |
A new index of a char |
| [1] |
bool |
Is code commented or not |
_canGetSymbol
function _canGetSymbol(uint256 _index, string _program) internal pure returns (bool)
Checks if it is possible to get next char from a _program
Parameters
| Name |
Type |
Description |
| _index |
uint256 |
is a current index of a char |
| _program |
string |
is a current program string |
Return Values
| Name |
Type |
Description |
| [0] |
bool |
True if program has the next symbol, otherwise is false |
_nonEmptyArrLen
function _nonEmptyArrLen(string[] _arr) internal pure returns (uint256 i)
Returns the length of a string array excluding empty elements
Ex. nonEmptyArrLen['h', 'e', 'l', 'l', 'o', '', '', '']) == 5 (not 8)
Parameters
| Name |
Type |
Description |
| _arr |
string[] |
Input string array |
Return Values
| Name |
Type |
Description |
| i |
uint256 |
The legth of the array excluding empty elements |