| 1 | # YSH specific features of eval
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| 2 | 
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| 3 | ## our_shell: ysh
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| 4 | ## oils_failures_allowed: 1
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| 5 | 
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| 6 | #### Eval does not take a literal block - can restore this later
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| 7 | 
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| 8 | var b = ^(echo obj)
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| 9 | eval (b)
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| 10 | 
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| 11 | eval (^(echo command literal))
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| 12 | 
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| 13 | # Doesn't work because it's a positional arg
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| 14 | eval { echo block }
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| 15 | 
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| 16 | ## status: 3
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| 17 | ## STDOUT:
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| 18 | obj
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| 19 | command literal
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| 20 | ## END
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| 21 | 
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| 22 | 
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| 23 | #### Eval a block within a proc
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| 24 | proc run (;;; block) {
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| 25 |   eval (block)
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| 26 | }
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| 27 | 
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| 28 | run {
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| 29 |   echo 'In a block!'
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| 30 | }
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| 31 | ## STDOUT:
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| 32 | In a block!
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| 33 | ## END
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| 34 | 
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| 35 | #### Eval block created by calling a proc
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| 36 | proc lazy-block ( ; out; ; block) {
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| 37 |   call out->setValue(block)
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| 38 | }
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| 39 | 
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| 40 | var myglobal = 0
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| 41 | 
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| 42 | lazy-block (&my_block) {
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| 43 |   json write (myglobal)
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| 44 | }
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| 45 | 
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| 46 | eval (my_block)
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| 47 | setvar myglobal = 1
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| 48 | eval (my_block)
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| 49 | ## STDOUT:
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| 50 | 0
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| 51 | 1
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| 52 | ## END
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| 53 | 
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| 54 | #### eval (block) can read variables like eval ''
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| 55 | 
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| 56 | proc p2(code_str) {
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| 57 |   var mylocal = 42
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| 58 |   eval $code_str
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| 59 | }
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| 60 | 
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| 61 | p2 'echo mylocal=$mylocal'
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| 62 | 
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| 63 | proc p (;;; block) {
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| 64 |   var mylocal = 99
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| 65 |   eval (block)
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| 66 | }
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| 67 | 
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| 68 | p {
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| 69 |   echo mylocal=$mylocal
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| 70 | }
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| 71 | 
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| 72 | 
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| 73 | ## STDOUT:
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| 74 | mylocal=42
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| 75 | mylocal=99
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| 76 | ## END
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| 77 | 
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| 78 | #### eval should have a sandboxed mode
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| 79 | 
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| 80 | proc p (;;; block) {
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| 81 |   var this = 42
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| 82 | 
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| 83 |   # like push-registers?  Not sure
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| 84 |   # We could use state.ctx_Temp ?  There's also ctx_FuncCall etc.
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| 85 |   #
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| 86 |   # I think we want to provide full control over the stack.
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| 87 |   push-frame {
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| 88 |     eval (block)
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| 89 |   }
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| 90 | }
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| 91 | 
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| 92 | p {
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| 93 |   echo $this
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| 94 | }
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| 95 | 
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| 96 | ## status: 1
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| 97 | ## STDOUT:
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| 98 | TODO
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| 99 | ## END
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