sleep.engine

Class Block

Implemented Interfaces:
Serializable

public class Block
extends Object
implements Serializable

A Block is the fundamental unit of parsed and ready to execute sleep code.

To execute a block of code:

 ScriptInstance    script; // asume
 Block             code;   // assume
 
 ScriptEnvironment env   = script.getEnvironment();  
 Scalar            value = SleepUtils.runCode(code, env);
 

The variable value would contain the return value after the block was executed. It is recommended blocks only be run using SleepUtils.runCode() as there is a little bit of synchronization and cleanup that has to be done prior to and after executing a block of code.

See Also:
Scalar, ScriptEnvironment, ScriptInstance

Field Summary

protected Step
first
our first step in this block
protected Step
last
our last step in this block
protected String
source
an identifier/tag/whatever identifying the source of this block (i.e.

Constructor Summary

Block(String _src)

Method Summary

void
add(Step n)
Scalar
evaluate(ScriptEnvironment environment)
evaluates this block of code.
Scalar
evaluate(ScriptEnvironment environment, Step start)
evaluates this block of code.
int
getApproximateLineNumber()
Returns an approximated line number for the steps in this block object...
String
getApproximateLineRange()
Returns an approximate range of line numbers for the steps in this block object.
int
getHighLineNumber()
return the highest line number associated with this block
int
getLowLineNumber()
return the lowest line number associated with this block
String
getSource()
Returns the source identifier for this block
String
getSourceLocation()
Returns a string representation of where in the source code this block originated from
String
toString()
Returns a string representation of the Abstract Syntax Tree (AST).
String
toString(String prefix)

Field Details

first

protected Step first
our first step in this block

last

protected Step last
our last step in this block

source

protected String source
an identifier/tag/whatever identifying the source of this block (i.e. somescript.sl)

Constructor Details

Block

public Block(String _src)

Method Details

add

public void add(Step n)

evaluate

public Scalar evaluate(ScriptEnvironment environment)
evaluates this block of code. please note that if the block has a return statement and the method clearReturn() is not called on the corresponding script environment chaos will ensue. use SleepUtils.runCode() to safely execute a block of code. don't call this method yourself. okay?

evaluate

public Scalar evaluate(ScriptEnvironment environment,
                       Step start)
evaluates this block of code. please note that if the block has a return statement and the method clearReturn() is not called on the corresponding script environment chaos will ensue. use SleepUtils.runCode() to safely execute a block of code. don't call this method yourself. okay?

getApproximateLineNumber

public int getApproximateLineNumber()
Returns an approximated line number for the steps in this block object... returns -1 if no code is in this block (unlikely)

getApproximateLineRange

public String getApproximateLineRange()
Returns an approximate range of line numbers for the steps in this block object. Useful for formatting error messages in script warnings and such.

getHighLineNumber

public int getHighLineNumber()
return the highest line number associated with this block

getLowLineNumber

public int getLowLineNumber()
return the lowest line number associated with this block

getSource

public String getSource()
Returns the source identifier for this block

getSourceLocation

public String getSourceLocation()
Returns a string representation of where in the source code this block originated from

toString

public String toString()
Returns a string representation of the Abstract Syntax Tree (AST). An AST represents how the sleep parser interpreted a script string

toString

public String toString(String prefix)