WebGLRenderingContext.getShaderSource()
  The WebGLRenderingContext.getShaderSource() method of the
  WebGL API returns the source code of a
  WebGLShader as a DOMString.
Syntax
DOMString gl.getShaderSource(shader);
Parameters
- shader
 - 
    
A
WebGLShaderobject to get the source code from. 
Return value
A DOMString containing the source code of the shader.
Examples
var shader = gl.createShader(gl.VERTEX_SHADER);
gl.shaderSource(shader, originalSource);
var source = gl.getShaderSource(shader);
Specifications
| Specification | 
|---|
| WebGL Specification  # 5.14.9  | 
Browser compatibility
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